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Universal Mathematics Codex & Active Review
Mathematics Codex & Vocabulary Hub
An all-in-one concordance of mathematics. Explore formal definitions, conceptual mechanisms, worked step-by-step procedures, and lesson vocabulary—with interactive formula solvers, 3D active recall flashcards, and audio speech pronunciation.
Interactive Formula Sandbox & Solver
Substitute variables to generate step-by-step mathematical proofs.
Card 1 of 195
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Showing 195 of 195 indexed mathematical concepts & vocabulary terms
A
A — Concepts & Terminology
15 terms
Absolute Value & The Integer Domain
/ˈæbsəluːt ˈvæljuː/ • Latin: "absolutus" (freed, unbound by direction)
Number Systems & ArithmeticGrade 6
Formal Definition & Axiom
The non-negative magnitude of a real number on the continuous number line, representing its geometric distance from origin zero ($0$) irrespective of direction.
Exemplar / Formula
$$|x| = \begin{cases} x & \text{if } x \ge 0 \ -x & \text{if } x < 0 \end{cases}$$
What It Does
It quantifies pure magnitude where direction or sign is irrelevant, such as deviations, financial deficits, depth below sea level, or physical distance.
How To Do It
1Locate the coordinate $x$ on the real number line.
2Measure the spatial distance between $x$ and $0$.
3Drop any negative sign: distance is always non-negative ($|-7| = 7$, $|+7| = 7$).
If a = b, then a + c = b + c for any real number c.
Exemplar / Formula
$$\text{If } a = b, \text{ then } a + c = b + c$$
Addition Regrouping & Decomposition (Carrying)
/riːˈɡruːpɪŋ/ • Old French: "groupe" (cluster or bundle)
Number Systems & ArithmeticGrade 2
Formal Definition & Axiom
The algorithmic process of composing a single higher base-ten unit whenever the sum of digits in an existing column equals or exceeds the base value ($10$).
It preserves place value integrity by ensuring no single digit slot ever exceeds $9$, allowing infinite multi-digit addition.
How To Do It
1Align addends vertically by column (Hundreds, Tens, Ones).
2Add the Ones column. If the sum is 10 or greater, record the ones digit below and carry the tens bundle above the next column.
3Add the Tens column, remembering to include any carried bundle.
Worked Exemplum
Problem: Compute $48 + 37$ with vertical regrouping.
Solution: Ones: $8 + 7 = 15$. Record 5 in ones, carry 1 ten. Tens: $1 \text{ (carried)} + 4 + 3 = 8$. Final sum: $85$.
Q.E.D. ∎
Advanced Factoring Strategies for Quadratic Expressions
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
Algebraic Identity
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An equality relation A = B such that A and B evaluate to the same value for all possible values of their variables.
Algebraic Model
Descriptive StatisticsGrade 9
Formal Definition & Axiom
A mathematical representation using variables and operations to simulate real-world behaviors and make predictions.
Analyzing a Graph
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 5: A Synthesis of Modeling with Equations and Functions, Elements of Modeling.
Analyzing a Verbal Description
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 5: A Synthesis of Modeling with Equations and Functions, Elements of Modeling.
Analyzing Data Collected on Two Variables
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Numerical Data on Two Variables.
The total two-dimensional surface enclosed within a closed boundary, quantified as the aggregate count of square unit tiles ($1 \times 1$) that tile the planar region without overlaps.
Exemplar / Formula
$$A = l \times w = b \times h$$
What It Does
It measures planar coverage: flooring, carpeting, painting walls, solar panel arrays, and farming plots.
How To Do It
1Measure the perpendicular linear length ($l$) and linear width ($w$) in matching units.
2Multiply length by width: $A = l \times w$.
3Attach square units to the product ($\text{in}^2, \text{cm}^2, \text{m}^2$).
Worked Exemplum
Problem: A classroom rug measures $8\text{ ft}$ long and $6\text{ ft}$ wide. Calculate the total floor area covered.
Solution: $A = l \times w = 8 \times 6 = 48\text{ sq ft}$.
Q.E.D. ∎
Arithmetic sequence
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A sequence is called arithmetic if there is a real number d such that each term in the sequence is the sum of the previous term and d.
Ask students
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
How can a graph be used to make a prediction? Estimate the value from the line or curve.
Associative Property
Polynomials & Algebraic ExpressionsGrade 9
Formal Definition & Axiom
The property stating that the grouping of numbers being added or multiplied does not change the result: (a + b) + c = a + (b + c) and (ab)c = a(bc).
Average Rate of Change
Linear & Piecewise FunctionsGrade 9
Formal Definition & Axiom
The change in the dependent variable (elevation) divided by the change in the independent variable (time) over a given interval. Graphically, this is the slope of the line segment.
Geometric postulates establishing that two triangles possess identical size and shape if a specific subset of corresponding sides and angles are proven equal.
It allows rigorous mathematical proof: once two triangles are proven congruent by 3 pieces of criteria, all 6 corresponding parts are guaranteed congruent (CPCTC).
How To Do It
1Identify given information and mark congruent side and angle pairs on the diagram.
2Look for shared sides (Reflexive Property) or vertical angles.
3Match to a valid congruence criteria (SSS, SAS, ASA, AAS, or Hypotenuse-Leg for right triangles). Never use unproven configurations like SSA or AAA.
Worked Exemplum
Problem: Two triangles share side $AC$. Side $AB \cong AD$ and $\angle BAC \cong \angle DAC$. Prove $\Delta ABC \cong \Delta ADC$.
Solution: $AB \cong AD$ (Side), $\angle BAC \cong \angle DAC$ (Angle), and $AC \cong AC$ (Side via Reflexive Property). Triangles are congruent by $\text{SAS Congruence Postulate}$.
Q.E.D. ∎
B
B — Concepts & Terminology
6 terms
Base Multiplier (b)
Exponential FunctionsGrade 9
Formal Definition & Axiom
The constant factor by which the function value is multiplied each time $x$ increases by 1 unit. When $b > 1$, the function models growth; when $0 < b < 1$, it models exponential decay.
The value of a digit determined strictly by its position within a number, where each unit in the tens column equals an aggregate group of ten individual single units.
Exemplar / Formula
$$\text{Two-Digit Number} = (T \times 10) + (O \times 1)$$
What It Does
It allows humans to express any quantity using only ten symbols ($0$ through $9$) by bundling groups into bundles of ten, avoiding the need for infinite distinct numeral marks.
How To Do It
1Count out the total single units into complete bundles of ten.
2Write the count of complete 10-bundles in the left column (Tens).
3Write any remaining loose single units in the right column (Ones).
Worked Exemplum
Problem: Decompose the quantity $47$ into its foundational base-ten components.
Solution: 47 contains 4 bundles of ten and 7 loose units: $47 = (4 \times 10) + (7 \times 1) = 40 + 7$.
It bypasses manual, error-prone repeated polynomial multiplications (like multiplying $(a+b)$ five times), expanding higher-degree powers in a single structured sweep.
How To Do It
1Identify row $n$ in Pascal's Triangle to obtain coefficients $\binom{n}{k}$.
2Write descending powers of $a$ from $a^n$ down to $a^0$.
3Write ascending powers of $b$ from $b^0$ up to $b^n$.
4Multiply coefficients and variable powers together for each term.
Worked Exemplum
Problem: Expand $(x + 2)^3$ using the Binomial Theorem.
Geometric relationships for any Euclidean circle, where Circumference ($C$) is the boundary perimeter and Area ($A$) is the internal planar surface, both governed by the transcendental constant $\pi \approx 3.14159$.
Exemplar / Formula
$$C = 2\pi r = \pi d, \quad A = \pi r^2$$
What It Does
It allows precise calculation of round perimeters (wheels, tracks) and circular surface areas (pipes, pizza slices, fields) from a single radial measurement.
How To Do It
1Identify radius ($r$). If given diameter ($d$), divide by $2$ ($r = d/2$).
When grouping students, consider their reading skill.
Closed Circle
Equations & InequalitiesGrade 9
Formal Definition & Axiom
A solid filled dot on a number line representing an inclusive boundary that is included in the solution set (≤ or ≥).
Closure
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A set has closure under an operation if performing that operation on members of the set always produces a member of the same set. Polynomials are closed under addition and subtraction.
Cody
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
I am thinking of a plus 2 pattern, so it continues 10, 12, 14, 16, ….
Coefficient
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The numerical multiplicative factor preceding a variable in an algebraic term (e.g., 5 in 5x²).
Combined Rate
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The total operational output rate achieved when multiple independent agents or machines work concurrently.
Common error
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Students may subtract 16 outside of the parentheses to balance the +16 inside in Opening Exercise 2.
Commutative Property
/kəˈmjuːtətɪv/ • Latin: "commutare" (to interchange or swap)
The property stating that the order in which two real numbers are added or multiplied does not change the result: a + b = b + a and ab = ba.
Exemplar / Formula
$$a + b = b + a$$
What It Does
It halves the memory required for mental math fact fluency: if you know $3 + 8 = 11$, you automatically know $8 + 3 = 11$.
How To Do It
1Identify the two addends being combined.
2Start with the larger number first to minimize manual counting efforts (Count-On Strategy).
3Add the smaller addend: the resulting sum is invariant.
Worked Exemplum
Problem: Calculate $2 + 9$ using the Commutative Property.
Solution: Swap addends: $2 + 9 = 9 + 2$. Count on 2 units from 9: $9 \to 10 \to 11$. Sum is $11$.
Q.E.D. ∎
Comparing Distributions
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Calculating and Interpreting Measures of Center and Variability.
Comparing Quadratic, Square Root, and Cube Root Functions Represented in Different Ways
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Function Transformations and Modeling.
Completing the Square
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Using Different Forms for Quadratic Functions.
Complex Numbers & The Imaginary Unit
/ˈkɒm.plɛks/ • Latin: "complexus" (interwoven, composite of real and imaginary)
Algebraic Foundations & ModelingGrade 11
Formal Definition & Axiom
An extension of the one-dimensional real number system into a two-dimensional complex plane ($\mathbb{C}$), defined by the imaginary unit $i$ whose square equals $-1$.
Exemplar / Formula
$$z = a + bi \quad (i = \sqrt{-1}, \; i^2 = -1, \; a, b \in \mathbb{R})$$
What It Does
It eliminates the barrier of negative square roots, guaranteeing that every $n$-th degree polynomial has exactly $n$ complex roots (Fundamental Theorem of Algebra). Powers electrical engineering and quantum physics.
How To Do It
1Treat $i$ algebraically like a variable, combining real parts with real parts and imaginary parts with imaginary parts: $(a + bi) + (c + di) = (a+c) + (b+d)i$.
2When multiplying, expand via FOIL and replace any occurrence of $i^2$ with $-1$.
3To divide, multiply numerator and denominator by the complex conjugate $a - bi$.
An inequality formed by joining two individual inequalities with the connective word 'and' or 'or'.
Conditional Relative Frequencies and Association
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Categorical Data on Two Variables.
Conjunction ('And')
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A compound sentence that is true only if both of its component statements are simultaneously true. Corresponding to set intersection (∩).
Constraint
Descriptive StatisticsGrade 9
Formal Definition & Axiom
A condition or restriction that must be satisfied by the solutions of a mathematical model.
Creating and Solving Quadratic Equations in One Variable
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
Cumulative Volume
Descriptive StatisticsGrade 9
Formal Definition & Axiom
The total aggregated quantity of water used up to a specified point in time.
D
D — Concepts & Terminology
12 terms
Data Source
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Core Math Tools, http://nctm.
Deductive Reasoning
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A logical process in which a conclusion is based on the concordance of multiple premises that are assumed or proven to be true.
Degree of a Polynomial
Polynomials & Algebraic ExpressionsGrade 9
Formal Definition & Axiom
The highest exponent of the variable in any term of the polynomial (when in one variable).
Degree Sum Theorem
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
For non-zero polynomials P and Q, deg(P · Q) = deg(P) + deg(Q).
Dependent Variable
Linear & Piecewise FunctionsGrade 9
Formal Definition & Axiom
The output value of a function, which depends on the input value (usually elevation/height, graphed on the vertical axis).
Derivative via Difference Quotient
/dɪˈrɪvətɪv/ • Latin: "derivare" (to draw off from a source stream)
Calculus & AnalysisGrade 12
Formal Definition & Axiom
The instantaneous rate of change of a differentiable continuous function with respect to its independent variable, geometrically representing the exact slope of the tangent line at any point $x$.
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Using Different Forms for Quadratic Functions.
Describing the Center of a Distribution
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Shapes and Centers of Distributions.
Disjoint Sets
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Two sets that have no elements in common (their intersection is empty).
Disjunction ('Or')
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A compound sentence that is true if at least one of its component statements is true. Corresponding to set union (∪).
Distributive Property
/dɪˈstrɪbjʊtɪv/ • Latin: "distribuere" (to apportion or divide up)
The mathematical axiom asserting that multiplying a sum by a number gives the same result as multiplying each addend separately and adding the products: a(b + c) = ab + ac.
Exemplar / Formula
$$a(b + c) = ab + ac \quad \text{and} \quad (b + c)a = ba + ca$$
What It Does
It allows complex mental arithmetic by breaking intimidating numbers (like $7 \times 14$) into two effortless friendly facts ($7 \times 10 + 7 \times 4$).
How To Do It
1Break one tough factor into two easier additive parts (e.g., $14 = 10 + 4$).
2Multiply the outside multiplier by the first decomposed part.
3Multiply the outside multiplier by the second decomposed part.
4Add the two partial products together.
Worked Exemplum
Problem: Evaluate $8 \times 13$ using the Distributive Property.
Two algebraic expressions that yield the exact same numerical result whenever the same values are substituted for their variables.
Equivalent Systems
Equations & InequalitiesGrade 9
Formal Definition & Axiom
Two systems of equations that have the exact same solution set.
Estimating Centers and Interpreting the Mean as a Balance Point
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Shapes and Centers of Distributions.
Euclidean Division Algorithm (Long Division)
/lɔːŋ dɪˈvɪʒən/ • Latin: "divisio" (distribution among shares)
Number Systems & ArithmeticGrade 4
Formal Definition & Axiom
An iterative place-value algorithm that determines how many times a positive integer divisor ($b$) partitions into a dividend ($a$), yielding an integer quotient ($q$) and an exact remainder ($r$).
Exemplar / Formula
$$a = bq + r \quad (0 \le r < b)$$
What It Does
It enables the exact and step-by-step division of arbitrarily large multi-digit numbers by breaking the computation down column-by-column.
How To Do It
1Divide: Determine how many times the divisor fits into the current active place-value digit(s).
2Multiply: Multiply the resulting quotient digit by the divisor.
3Subtract: Subtract that product from the active digits to find the local remainder.
4Bring Down: Bring down the next digit of the dividend and repeat.
Worked Exemplum
Problem: Divide $496 \div 4$ using the standard long division algorithm.
Solution: $4 \div 4 = 1$ (rem 0). Bring down 9: $9 \div 4 = 2$ ($2 \times 4 = 8$, rem 1). Bring down 6: $16 \div 4 = 4$ ($4 \times 4 = 16$, rem 0). Quotient is $124$.
Q.E.D. ∎
Explicit (Closed-Form) Formula
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A formula allowing direct calculation of the nth term of a sequence using only the index n, without computing any preceding terms.
Explore the following question
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
How would the relative frequencies look if males and females had the same opinions about their favorite superpowers? This question is a prelude to Lesson 11.
Exponential Decay
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Linear and Exponential Sequences.
Exponential Function
Exponential FunctionsGrade 9
Formal Definition & Axiom
A function in which an independent variable appears as an exponent: $f(x) = a \cdot b^x$. The rate of change increases directly in proportion to the magnitude of the function value itself.
Exemplar / Formula
$$f(x) = a \cdot b^x \quad (a \ne 0, \, b > 0, \, b \ne 1)$$
Exponential Growth & Decay Models
/ˌɛkspəˈnɛnʃəl/ • Latin: "exponere" (to exhibit, put forth into powers)
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A non-linear mathematical model where the rate of change is proportional to the current amount, resulting in geometric compounding over continuous or discrete time intervals $t$.
It solves any parabolic or quadratic equation, even when factoring fails. It models trajectories, projectiles, revenue optimization, and physics mechanics.
How To Do It
1Set equation into standard form: $ax^2 + bx + c = 0$.
2Identify coefficients $a, b, c$ with their respective signs.
During this phase of the lesson, students should work in small groups.
For the equation
Equations & InequalitiesGrade 9
Formal Definition & Axiom
I first looked for the function type, which narrowed my search considerably.
For the graph
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
I looked at the overall shape first to identify what type of graph it was (quadratic, linear, exponential, piecewise, square root, or cube root).
Four Interesting Transformations of Functions
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Transformations of Functions.
Fraction Addition with Unlike Denominators
/ʌnˈlaɪk dɪˈnɒmɪneɪtərz/ • Latin: "denominare" (to name or specify)
Fractions & Rational NumbersGrade 5
Formal Definition & Axiom
The method of renaming fractions into equivalent representations sharing a common unit measure (the Least Common Denominator) prior to combining numerators.
Fractions cannot be added directly if their pieces are different sizes (e.g. halves and thirds); finding the LCD cuts all pieces into identical units so they can be summed.
How To Do It
1Find the Least Common Multiple (LCM) of denominators $b$ and $d$.
2Multiply numerator and denominator of each fraction by the factor needed to attain the LCD.
3Add the newly aligned numerators while keeping the common denominator constant.
Fraction Division via Reciprocal (Keep-Change-Flip)
/rɪˈsɪprəkəl/ • Latin: "reciprocus" (moving back and forth, alternating)
Fractions & Rational NumbersGrade 6
Formal Definition & Axiom
An algebraic law establishing that dividing by a rational fraction is mathematically equivalent to multiplying by its multiplicative inverse (reciprocal).
Division answers "how many groups fit inside." Multiplying by the flipped reciprocal counts how many sub-units fit without laborious manual partitioning.
How To Do It
1Keep: Leave the dividend (first fraction) unchanged.
2Change: Invert the division operator ($\div$) into multiplication ($\times$).
3Flip: Invert the divisor (second fraction) into its reciprocal ($\frac{c}{d} \to \frac{d}{c}$).
A function is a correspondence between two sets, X and Y, in which each element of X is matched to one and only one element of Y.
Fundamental Theorem of Calculus (FTC)
/ˌfʌndəˈmɛntl ˈθɪərəm/ • Latin: "fundamentum" (groundwork, base cornerstone)
Calculus & AnalysisGrade 12
Formal Definition & Axiom
The unifying theorem of mathematical analysis demonstrating that differentiation and integration are inverse operations: the definite integral (net accumulated area) can be calculated via anti-derivatives.
It bridges geometry (accumulating area under curves) with algebra (reversing derivatives), enabling exact calculation of areas, volumes of revolution, and total physical work.
How To Do It
1Find the antiderivative function $F(x)$ such that $F'(x) = f(x)$.
2Evaluate the antiderivative at the upper integration limit ($F(b)$).
3Evaluate the antiderivative at the lower integration limit ($F(a)$).
4Subtract: $\text{Net Area} = F(b) - F(a)$.
Worked Exemplum
Problem: Evaluate the definite integral $\int_{0}^{3} 2x \, dx$.
A geometric sequence goes from one term to the next by multiplying (or dividing) by the same value.
Graphing Cubic, Square Root, and Cube Root Functions
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Function Transformations and Modeling.
Graphing Quadratic Functions from Factored Form, f(x)=a(x-m)(x-n)
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
Graph of an Equation
Equations & InequalitiesGrade 9
Formal Definition & Axiom
The set of all points on the coordinate plane whose coordinates (x, y) satisfy the equation.
Graphs Can Solve Equations Too
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Transformations of Functions.
Graphs Example
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Graphs Data are often summarized by graphs; the graphs are the first indicator of variability in the data.
Greatest Common Factor (GCF) & Euclidean Algorithm
The largest natural number that evenly divides two or more integers without leaving a remainder, forming the basis of simplifying fractions.
Exemplar / Formula
$$\gcd(a, b) = \gcd(b, a \bmod b) \quad (\gcd(a, 0) = a)$$
What It Does
It finds the maximum bundle size when grouping disparate collections into identical subsets, and reduces fractions to their simplest indivisible terms.
How To Do It
1Find the prime factorizations of both numbers.
2Identify all common prime factors shared by both sets.
3Multiply the shared common prime factors together to obtain the GCF.
Worked Exemplum
Problem: Find the Greatest Common Factor of $24$ and $36$.
Solution: Prime factorization: $24 = 2^3 \times 3$, $36 = 2^2 \times 3^2$. Common prime factors: $2^2 \times 3 = 4 \times 3 = 12$. $\text{GCF} = 12$.
Q.E.D. ∎
H
H — Concepts & Terminology
4 terms
Half-Plane
Equations & InequalitiesGrade 9
Formal Definition & Axiom
The region of a coordinate plane on one side of an infinite boundary line.
Histograms
Descriptive StatisticsGrade 9
Formal Definition & Axiom
A graph of data that groups the data based on intervals and represents the data in each interval by a bar.
Horizontal Asymptote
Exponential FunctionsGrade 9
Formal Definition & Axiom
A horizontal line ($y = 0$ for basic exponential curves) that the curve approaches closer and closer as $x \to -\infty$, but never intersects or passes.
Exemplar / Formula
$$y = 0 \quad \text{as } x \to -\infty \text{ for } f(x) = 2^x$$
Horizontal Plateau
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A segment where slope m = 0, indicating zero flow rate or usage.
I
I — Concepts & Terminology
14 terms
Identity
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An equation that evaluates to True for all possible values of its variables (e.g., 2(x + 1) = 2x + 2).
If f
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
R→R is the function such that x↦x^{2}, then the range of f is the set of all nonnegative real numbers.
If not
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Notice that in the next table in your packet (Brand A), the second row says "Deviation from the Mean.
Important
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Sequences can be indexed by starting with any integer.
Indefinite Integrals & Antidifferentiation
/ˈɪndɛfɪnɪt ˈɪntɪɡrəl/ • Latin: "integrare" (to make whole, aggregate)
Calculus & AnalysisGrade 12
Formal Definition & Axiom
The complete family of antiderivative functions whose instantaneous derivative equals the integrand $f(x)$, unified by the arbitrary constant of integration $C$.
The input value of a function, which changes independently (usually time, graphed on the horizontal axis).
Inequality
Equations & InequalitiesGrade 9
Formal Definition & Axiom
A mathematical statement comparing two expressions using relation symbols <, ≤, >, or ≥.
Inequality Reversal Property
Equations & InequalitiesGrade 9
Formal Definition & Axiom
If a < b and c < 0, then ac > bc. Multiplying or dividing both sides of an inequality by a negative number reverses the direction of the inequality symbol.
Initial Term
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The starting value a_0 (or a_1) required to initiate the evaluation of a recursive process.
Initial Value (a)
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The value of the function when $x = 0$, representing the $y$-intercept. Because any nonzero base raised to the power of 0 equals 1 ($b^0 = 1$), $f(0) = a \cdot 1 = a$.
Exemplar / Formula
$$f(0) = a \cdot b^0 = a$$
Interpreting Correlation
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Numerical Data on Two Variables.
Interpreting Quadratic Functions from Graphs and Tables
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
Interpreting the Standard Deviation
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Calculating and Interpreting Measures of Center and Variability.
Intersection
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The set of elements belonging to both sets A and B (A ∩ B).
L
L — Concepts & Terminology
10 terms
Least Common Denominator (LCD)
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The least common multiple of the denominators of a set of fractions.
Let f
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
R→R be the function such that x↦x^{2}.
Linear and Exponential Models—Comparing Growth Rates
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Functions and Their Graphs.
LinearB
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
ExponentialC: Quadratic I looked at the difference in each output.
Linear Combination
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
An expression constructed from a set of terms by multiplying each term by a constant and adding the results.
Linear Slope-Intercept Form
/sloʊp ˈɪntərsɛpt/ • Latin: "intercipere" (to catch or cross between)
Algebraic Foundations & ModelingGrade 8
Formal Definition & Axiom
The canonical algebraic representation of a two-dimensional straight line, where $m$ signifies the constant rate of change (slope) and $b$ represents the coordinate value where the line intercepts the vertical y-axis ($(0, b)$).
It enables instant graphing and prediction of linear behaviors, allowing you to project future outcomes with a known starting point ($b$) and velocity ($m$).
How To Do It
1Calculate the slope $m$ by finding vertical change over horizontal change: $m = \frac{y_2 - y_1}{x_2 - x_1}$.
2Plot the starting y-intercept $(0, b)$ directly on the vertical axis.
3Use slope $m = \frac{\text{rise}}{\text{run}}$ to navigate from the intercept to subsequent points, and connect with a line.
Worked Exemplum
Problem: Find the slope-intercept equation of the line passing through $(2, 5)$ and $(4, 11)$.
The inverse mathematical function of exponentiation, answering the question: "To what exponent must the base $b$ be raised to produce the value $x$?"
Exemplar / Formula
$$\log_b(x) = y \iff b^y = x \quad (\log(xy) = \log x + \log y)$$
What It Does
It compresses astronomical multiplicative scales into manageable linear steps (Richter scale earthquakes, pH acidity, decibels of sound, compound interest).
How To Do It
1Product Rule: Sum of logs equals log of product: $\log(A) + \log(B) = \log(AB)$.
2Quotient Rule: Difference of logs equals log of quotient: $\log(A) - \log(B) = \log(A/B)$.
3Power Rule: Pull exponents out front as multipliers: $\log(A^k) = k \log(A)$.
Worked Exemplum
Problem: Condense into a single logarithm: $2\log_3(x) + \log_3(5)$.
What do you notice about the three sets of data? Can you identify the type of function they represent? Students may observe some of the examples listed below.
Lost Solution
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A valid solution that is accidentally eliminated by an invalid operation (such as dividing both sides by a variable expression that equals zero).
M
M — Concepts & Terminology
11 terms
Marginal Tax Rate
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The tax rate applied to the last dollar of income earned within a specific bracket.
Mathematical Modeling
Descriptive StatisticsGrade 9
Formal Definition & Axiom
The process of choosing and using appropriate mathematics and statistics to analyze empirical situations, to understand them better, and to improve decisions.
Measures of Center: Mean, Median & Mode
/miːn ˈmiːdiən moʊd/ • Latin: "medianus" (of the middle)
Number Systems & ArithmeticGrade 6
Formal Definition & Axiom
Statistical metrics summarizing an entire data distribution into a single representative central value: the arithmetic average (Mean), the 50th percentile midpoint (Median), and the most frequent value (Mode).
It distills large, noisy empirical datasets into actionable benchmark summaries for test scores, scientific experiments, climate averages, and economic indicators.
How To Do It
1Mean: Sum all values together, then divide by the total count $n$.
2Median: Arrange data in ascending numerical order and pick the exact middle value (or average the two middle values if $n$ is even).
3Mode: Identify the number that appears with highest frequency.
Worked Exemplum
Problem: Calculate the mean and median for the test score dataset: $\{80, 85, 90, 90, 100\}$.
Solution: Mean: $\frac{80+85+90+90+100}{5} = \frac{445}{5} = 89$. Median: Ordered middle value is $90$. Mode is $90$.
Q.E.D. ∎
Measuring Variability for Skewed Distributions (Interquartile Range)
Linear & Piecewise FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Calculating and Interpreting Measures of Center and Variability.
Measuring Variability for Symmetrical Distributions
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Calculating and Interpreting Measures of Center and Variability.
Modeling a Context from a Verbal Description
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 5: A Synthesis of Modeling with Equations and Functions, Completing the Modeling Cycle.
Modeling a Context from Data
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 5: A Synthesis of Modeling with Equations and Functions, Completing the Modeling Cycle.
Modeling Relationships with a Line
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Numerical Data on Two Variables.
More on Modeling Relationships with a Line
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Numerical Data on Two Variables.
Multiplication Property of Equality
Equations & InequalitiesGrade 9
Formal Definition & Axiom
If a = b, then ac = bc for any real number c.
Exemplar / Formula
$$\text{If } a = b, \text{ then } a \cdot c = b \cdot c$$
Multiplying and Factoring Polynomial Expressions
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
N
N — Concepts & Terminology
5 terms
Newton's Law of Cooling
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Using Functions and Graphs to Solve Problems.
Non-Permissible Value
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Any real number that causes a denominator in an expression to equal zero, making the expression undefined.
Note about lesson pace
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Just like the last lesson, use the fact that the examples are very similar to reduce the amount of writing on the board.
Note about the lesson pace
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Every new example or exercise in this lesson usually inserts just one more line of pseudocode into the previous exercise or example.
Now show a data plot for each
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Now can you see the trends more clearly? Yes, it is obvious that the first is linear.
O
O — Concepts & Terminology
5 terms
Objects in Motion
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Any object that is free falling or projected into the air without a power source is under the influence of gravity.
Open Circle
Equations & InequalitiesGrade 9
Formal Definition & Axiom
A hollow dot on a number line representing an exclusive boundary that is not included in the solution set (< or >).
Opening Exercise Scaffolding
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
If students are struggling with the type of function, have them plot the points.
Ordered Pair
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A pair of numbers (x, y) written in a specific order representing a unique point on a coordinate plane.
The universal algebraic precedence convention dictating the precise sequence in which arithmetic operations must be evaluated to ensure unambiguous solutions.
Core mathematical concept established in Module 3: Linear and Exponential Functions, Using Functions and Graphs to Solve Problems.
Piecewise Functions
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Transformations of Functions.
Piecewise Linear Function
Linear & Piecewise FunctionsGrade 9
Formal Definition & Axiom
A function defined by multiple linear segments, each covering a specific interval of time or domain. The overall graph looks like joined straight lines with corners.
A single point on the coordinate plane where two lines cross, representing the simultaneous solution.
Polynomial
Polynomials & Algebraic ExpressionsGrade 9
Formal Definition & Axiom
An expression consisting of variables and coefficients, constructed using only addition, subtraction, multiplication, and non-negative integer exponentiation.
Pose these questions
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Why does the first scatter plot result in an arch shape in the residual plot? The points in the scatter plot are not in a straight line.
An operational shortcut derived from the binomial theorem and difference quotient that computes the instantaneous rate of change of any monomial power function in a single algebraic step.
Exemplar / Formula
$$\frac{d}{dx}\left[x^n\right] = n x^{n - 1} \quad (n \in \mathbb{R})$$
What It Does
It bypasses lengthy limit difference quotient algebra, reducing derivative computation on polynomials to elementary mental arithmetic.
How To Do It
1Bring the existing exponent $n$ down in front to multiply the term.
2Subtract exactly $1$ from the power exponent ($n \to n - 1$).
3If the term has a leading constant $c$, multiply: $\frac{d}{dx}[c x^n] = c \cdot n x^{n-1}$.
A natural number greater than $1$ is Prime if its only positive divisors are $1$ and itself. A number with more than two distinct positive factors is Composite.
Specifies the domain of the variable of x to be the set of integers.
Pythagorean Theorem
/pɪˌθæɡəˈriːən/ • Named after Pythagoras of Samos (c. 570–495 BC)
Geometry & MeasurementGrade 8
Formal Definition & Axiom
A fundamental theorem of Euclidean geometry stating that in any right triangle, the area of the square erected upon the hypotenuse ($c$) equals the combined sum of the areas of the squares erected upon legs $a$ and $b$.
Exemplar / Formula
$$a^2 + b^2 = c^2 \iff c = \sqrt{a^2 + b^2}$$
What It Does
It unlocks straight-line distance calculations across two dimensions, forming the basis of navigation, construction, computer graphics, and coordinate geometry.
How To Do It
1Verify the triangle contains an exact $90^\circ$ right angle.
2Identify the hypotenuse ($c$), which is strictly opposite the right angle.
3Square the two known sides. To solve for hypotenuse: $c = \sqrt{a^2 + b^2}$. To solve for a leg: $a = \sqrt{c^2 - b^2}$.
Worked Exemplum
Problem: A right triangle has legs of length $6\text{ cm}$ and $8\text{ cm}$. Find the length of hypotenuse $c$.
A polynomial function of degree 2 ($f(x) = ax^2 + bx + c$, with $a \neq 0$). Its graph forms a U-shaped parabola.
Exemplar / Formula
$$f(x) = ax^2 + bx + c \quad (a \ne 0)$$
R
R — Concepts & Terminology
11 terms
Rational Equation
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An equation containing at least one fraction whose denominator contains a variable expression.
Ray
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A continuous portion of the coordinate line extending indefinitely in one direction from an endpoint.
Recall
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
What does the graph of a quadratic equation look like?Remind students that when calculating squares in their calculator, they need to watch out for a common error: (-1)^{2}≠-1^{2}.
A geometric configuration of discrete objects aligned into identical horizontal rows and vertical columns, serving as the concrete foundation of multiplication.
Exemplar / Formula
$$\text{Total Items} = \sum_{i=1}^{r} c = r \times c$$
What It Does
It bridges counting single items to spatial two-dimensional grouping, proving that multiplication is rapid repeated addition.
How To Do It
1Count the number of horizontal lines (Rows, $r$).
2Count how many objects are situated in each single row (Columns, $c$).
3Add the row count $r$ times, or skip-count by $c$.
Worked Exemplum
Problem: Find the total items in an array containing $4$ rows with $5$ stars in each row.
Solution: Repeated addition of rows: $5 + 5 + 5 + 5 = 20$. The array contains exactly $20$ stars.
Q.E.D. ∎
Recurrence Relation
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An equation that expresses each element of a sequence as a function of the preceding elements (e.g., a_n = 2a_{n-1} + 5).
Recursive Formulas for Sequences
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Linear and Exponential Sequences.
Recursive Sequence
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A sequence of numbers where each term after the first is defined as a function of the preceding term(s).
Relationships Between Two Numerical Variables
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Numerical Data on Two Variables.
Reversible Step
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An algebraic operation that preserves the exact solution set, such that applying its inverse returns the original equation.
It enables the measurement of inaccessible heights and distances (surveying mountains, celestial navigation, architectural load angles) from a single angle and distance.
How To Do It
1Anchor your perspective at the acute reference angle $\theta$.
2Label the three sides: Hypotenuse (longest side opposite $90^\circ$), Opposite (across from $\theta$), and Adjacent (next to $\theta$).
3Select the matching ratio from SOH-CAH-TOA based on your known and unknown sides, then solve.
Worked Exemplum
Problem: In a right triangle, angle $\theta$ has an opposite side of $5\text{ cm}$ and hypotenuse of $13\text{ cm}$. Find $\sin\theta$ and $\tan\theta$.
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Quadratic Expressions, Equations, and Functions.
Speed-Time Graph
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A graph where vertical position represents instantaneous rate of motion.
Standard Form of a Polynomial
Polynomials & Algebraic ExpressionsGrade 9
Formal Definition & Axiom
A polynomial written such that its terms are placed in descending order of degree from left to right.
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Function Transformations and Modeling.
Subject of a Formula
Equations & InequalitiesGrade 9
Formal Definition & Axiom
The variable that is isolated by itself on one side of an equation with a coefficient of 1.
Substitution Method
Equations & InequalitiesGrade 9
Formal Definition & Axiom
An algebraic technique where one variable is isolated and substituted into the other equation.
Summarizing Bivariate Categorical Data
Descriptive StatisticsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 2: Descriptive Statistics, Categorical Data on Two Variables.
Suri
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
I am thinking of the units digits in the multiples of two, so it continues 2, 4, 6, 8, 0, 2, 4, 6, 8, ….
System of Linear Equations
Equations & InequalitiesGrade 9
Formal Definition & Axiom
A collection of two or more linear equations involving the same set of variables.
T
T — Concepts & Terminology
13 terms
Tabular Multiplication (Box Method)
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A geometric organizer where terms of one polynomial form rows and terms of the other form columns, computing all partial products systematically.
Target Inversion
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Setting an explicit sequence formula equal or unequal to a desired threshold target and solving backwards for the initial term.
Taxable Income
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The amount of gross income used to calculate tax liability, after subtracting allowable exemptions and deductions.
Term
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
A single mathematical number, variable, or product of numbers and variables separated by addition or subtraction operators.
Test Point
Equations & InequalitiesGrade 9
Formal Definition & Axiom
A coordinate pair (not on the boundary line) substituted into an inequality to determine which half-plane contains solutions.
Their comments are as follows
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
Callie: It looks like the U.
The notation f
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
X→Y is used to name the function and describes both X and Y.
The Power of Exponential Growth
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Linear and Exponential Sequences.
Transformations of the Quadratic Parent Function, f(x)=x^{2}
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Function Transformations and Modeling.
Translating Graphs of Functions
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Function Transformations and Modeling.
Trinomial
/ˈfæk.tər.ɪŋ/ • Latin: "factor" (a maker, doer, or constituent part)
Polynomials & Algebraic ExpressionsGrade 9
Formal Definition & Axiom
A polynomial with exactly three terms, such as ax² + bx + c.
Exemplar / Formula
$$x^2 + (p + q)x + pq = (x + p)(x + q)$$
What It Does
By applying the Zero Product Property ($AB = 0 \implies A=0 \text{ or } B=0$), factoring converts complex polynomial expressions into simple solvable linear equations.
How To Do It
1Look for two integers $p$ and $q$ that multiply to constant $c$ ($p \times q = c$) and add to middle coefficient $b$ ($p + q = b$).
2Construct the binomials: $(x + p)(x + q)$.
3Check work by expanding via FOIL (First, Outside, Inside, Last).
Worked Exemplum
Problem: Factor the polynomial $x^2 + 7x + 12$.
Solution: Find two numbers that multiply to $12$ and add to $7$: $3 \times 4 = 12$ and $3 + 4 = 7$. Factored form: $(x + 3)(x + 4)$.
Q.E.D. ∎
Truth Value
Equations & InequalitiesGrade 9
Formal Definition & Axiom
The property of a mathematical sentence indicating whether it is True or False under a specific substitution.
Two-Way Frequency Table
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The relative frequency table would be found by dividing each of the above cell values by 450.
U
U — Concepts & Terminology
4 terms
Union
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The set of elements belonging to set A, set B, or both (A ∪ B).
Unit Fractions & Rational Partitioning
/ˈjuːnɪt ˈfrækʃən/ • Latin: "fractio" (a breaking into fragments)
Fractions & Rational NumbersGrade 3
Formal Definition & Axiom
A rational quantity formed by partitioning a single whole into $b$ congruent, equal-sized pieces, where the fraction represents exactly one of those partitioned segments.
It establishes the fundamental atomic building block of all rational numbers: any non-unit fraction $\frac{a}{b}$ is simply $a$ copies of the unit fraction $\frac{1}{b}$.
How To Do It
1Verify the whole unit is divided into segments of strictly equal size/length.
2Count the total number of segments to determine the denominator ($b$).
3Isolate or shade exactly 1 segment to represent $\frac{1}{b}$.
Worked Exemplum
Problem: Express the fraction $\frac{5}{8}$ as an iteration of its underlying unit fraction.
Solution: The unit fraction is $\frac{1}{8}$. Thus: $\frac{5}{8} = \frac{1}{8} + \frac{1}{8} + \frac{1}{8} + \frac{1}{8} + \frac{1}{8} = 5 \times \frac{1}{8}$.
Q.E.D. ∎
Unit Rate
/prəˌpɔːʃəˈnæləti/ • Latin: "pro portione" (according to the share)
Algebraic Foundations & ModelingGrade 9, Grade 7
Formal Definition & Axiom
A rate in which the second quantity in the comparison is one unit (e.g., 25 pages per minute).
Exemplar / Formula
$$y = kx \implies k = \frac{y}{x}$$
What It Does
It describes uniform rate behaviors: speed ($d = rt$), wage rates ($\text{Pay} = r \times \text{Hours}$), scaling recipes, and currency conversion.
How To Do It
1Pick any non-zero ordered coordinate pair $(x, y)$ from a proportional table or graph.
2Divide the dependent variable $y$ by independent variable $x$: $k = \frac{y}{x}$.
3Verify that all other pairs $(x_i, y_i)$ yield the identical quotient $k$.
Worked Exemplum
Problem: A car travels $165\text{ miles}$ in $3\text{ hours}$ at constant speed. Find the constant of proportionality and the equation relating distance ($y$) and hours ($x$).
Core mathematical concept established in Module 4: Polynomial and Quadratic Expressions, Equations, and Functions, Using Different Forms for Quadratic Functions.
V
V — Concepts & Terminology
3 terms
Velocity
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
The speed of an object in a given direction, corresponding to signed slope on a displacement graph.
Vertex
Quadratic Functions & EquationsGrade 9
Formal Definition & Axiom
The point where the graph of a quadratic function and its axis of symmetry intersect is called the vertex.
Volume of Rectangular Prisms
/ˈvɒljuːm/ • Latin: "volumen" (roll, scroll, 3D cubic capacity)
Geometry & MeasurementGrade 5
Formal Definition & Axiom
The total measure of three-dimensional space enclosed within a solid boundary, quantified as the aggregate number of unit cubes ($1 \times 1 \times 1$) that pack the interior without gaps.
Exemplar / Formula
$$V = l \times w \times h = B \times h$$
What It Does
It measures the physical capacity of solid 3D structures (such as storage containers, shipping boxes, or liquid tanks).
How To Do It
1Measure the length ($l$) and width ($w$) of the rectangular base to find base area ($B = l \times w$).
2Measure the perpendicular vertical height ($h$) of the prism.
3Multiply base area by height: $V = B \times h$. Units are always cubic ($\text{cm}^3, \text{in}^3, \text{m}^3$).
Worked Exemplum
Problem: Find the volume of a rectangular prism with length $6\text{ cm}$, width $4\text{ cm}$, and height $5\text{ cm}$.
Solution: $V = l \times w \times h = 6 \times 4 \times 5 = 24 \times 5 = 120\text{ cm}^3$.
Q.E.D. ∎
W
W — Concepts & Terminology
2 terms
Why Do Banks Pay YOU to Provide Their Services?
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Linear and Exponential Sequences.
Why Stay with Whole Numbers?
Exponential FunctionsGrade 9
Formal Definition & Axiom
Core mathematical concept established in Module 3: Linear and Exponential Functions, Functions and Their Graphs.
X
X — Concepts & Terminology
1 term
X of a function f
Algebraic Foundations & ModelingGrade 9
Formal Definition & Axiom
X→Y, then x is matched to an element of Y called f(x).
Z
Z — Concepts & Terminology
1 term
Zero-Product Property
Equations & InequalitiesGrade 9
Formal Definition & Axiom
If the product of two real numbers is zero, then at least one of the numbers must be zero: ab = 0 implies a = 0 or b = 0.
Exemplar / Formula
$$\text{If } A \cdot B = 0, \text{ then } A = 0 \text{ or } B = 0$$
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