Illustrative Math Alignment: Grade 8 Unit 3

Functions and Volume

Lesson 17: Scaling One Dimension

Use the following Media4Math resources with this Illustrative Math lesson.

Title	Body	Curriculum Topic
Definition--3D Geometry Concepts--Vertex	Vertex in 3D Geometry Topic 3D Geometry Definition A vertex is a point where three or more edges meet in a three-dimensional figure. Description In the study of three-dimensional geometry, the term vertex is fundamental. A vertex is a critical point in any 3D geometric shape, marking the intersection of edges. For example, in a cube, each corner where the edges converge is a vertex. Vertices are essential in defining the shape and structure of 3D figures, as they help in understanding the spatial relationships between different parts of the figure.	3-Dimensional Figures
Definition--3D Geometry Concepts--Vertical Cross-Sections of a Cone	Vertical Cross Sections of a Cone Topic 3D Geometry Definition A vertical cross section of a cone is the intersection of the cone with a plane that passes through its vertex and base, resulting in a two-dimensional shape.	Cones
Definition--3D Geometry Concepts--Vertical Cross-Sections of a Cylinder	Vertical Cross Sections of a Cylinder Topic 3D Geometry Definition A vertical cross-section of a cylinder is the intersection of the cylinder with a plane that is parallel to its axis. This cross-section is typically a rectangle if the plane cuts through the entire height of the cylinder.	Cylinders
Definition--3D Geometry Concepts--Vertical Cross-Sections of a Square Pyramid	Vertical Cross Sections of a Square Pyramid Topic 3D Geometry Definition A vertical cross section of a square pyramid is the intersection of the pyramid with a vertical plane that passes through its apex and base, resulting in a two-dimensional shape.	Pyramids
Definition--3D Geometry Concepts--Vertical Cross-Sections of a Triangular Prism	Vertical Cross Sections of a Triangular Prism Topic 3D Geometry Definition A vertical cross section of a triangular prism is a two-dimensional shape obtained by slicing the prism parallel to its height, revealing a triangular face.	Triangular Prisms
Definition--3D Geometry Concepts--Volume	Volume Topic 3D Geometry Definition Volume is the measure of the amount of space occupied by a three-dimensional object, expressed in cubic units. Description Volume is a fundamental concept in the study of three-dimensional geometry. It quantifies the capacity of a 3D object, indicating how much space it occupies. This measurement is crucial in various fields, including mathematics, engineering, architecture, and physical sciences.	Volume
Definition--3D Geometry Concepts--Cavalieri's Principle	Cavalieri's Principle Topic 3D Geometry Definition Cavalieri's Principle states that if two solids are contained between two parallel planes, and every plane parallel to these planes intersects both solids in cross-sections of equal area, then the two solids have equal volumes. Description Cavalieri's Principle is a fundamental concept in three-dimensional geometry that provides a method for determining the volume of solids. Named after the Italian mathematician Bonaventura Cavalieri, this principle is particularly useful for comparing the volumes of solids that might not have straightforward geometric shapes.	3-Dimensional Figures
Definition--Functions and Relations Concepts--Absolute Value Function	Absolute Value Function Topic Functions and Relations Definition An absolute value function is a function that contains an algebraic expression within absolute value symbols. It is defined as $$ f(x) = \|x\| $$ where \|x\| denotes the absolute value ofx. Description The absolute value function is significant in mathematics because it measures the distance of a number from zero on the number line, regardless of direction. This function is linear in nature, as it can be broken into two linear pieces: one for $$ x \geq 0 $$ and one for $$ x < 0 $$	Special Functions
Definition--Functions and Relations Concepts--Composite Function	Composite Function Topic Functions and Relations Definition A composite function is a function that is formed when one function is applied to the result of another function. Description Composite functions are significant in mathematics because they allow the combination of two functions to form a new function. This is denoted as (f∘g)(x) = f(g(x)). Composite functions are widely used in various fields, including computer science for function composition in programming and in calculus for chain rule applications. For example, if f(x) = 2x and g(x) = x + 3, then the composite function (f∘g)(x) = f(g(x)) = 2(x + 3) = 2x+6	Composite Functions
Definition--Functions and Relations Concepts--Conic Sections	Conic Sections Topic Functions and Relations Definition Conic sections are the curves obtained by intersecting a plane with a double-napped cone. Description Conic sections include circles, ellipses, parabolas, and hyperbolas, which are fundamental in the study of geometry and algebra. These shapes are described by quadratic equations and have numerous applications in physics, engineering, and astronomy. For example, the orbits of planets are ellipses, and parabolic mirrors are used in telescopes and satellite dishes. The general quadratic equation for conic sections is Ax2 + Bxy + Cy2 + Dx + Ey + F = 0	Conic Sections
Definition--Functions and Relations Concepts--Constant Function	Constant Function Topic Functions and Relations Definition A constant function is a function that always returns the same value, no matter the input. Description The constant function is one of the simplest types of functions in mathematics, expressed as f(x) = c	Relations and Functions
Definition--Functions and Relations Concepts--Continuous Function	Continuous Function Topic Functions and Relations Definition A continuous function is a function that does not have any breaks, holes, or gaps in its domain. Description Continuous functions are fundamental in calculus and mathematical analysis because they allow for the application of limits, derivatives, and integrals. A function f(x) is continuous if, for every point 𝑐 c in its domain, lim x→c f(x) = f(c)	Relations and Functions
Definition--Functions and Relations Concepts--Decreasing Function	Decreasing Function Topic Functions and Relations Definition A decreasing function is a function where the value of the function decreases as the input increases. Description Decreasing functions are important in mathematics because they describe scenarios where an increase in one variable leads to a decrease in another. This is mathematically represented as f(x1) > f(x2) for any 𝑥1 < 𝑥2	Relations and Functions
Definition--Functions and Relations Concepts--Dependent Variable	Dependent Variable Topic Functions and Relations Definition A dependent variable is a variable whose value depends on one or more other variables.	Relations and Functions
Definition--Functions and Relations Concepts--Discontinuous Function	Discontinuous Function Topic Functions and Relations Definition A discontinuous function is a function that has one or more points where it is not continuous.	Relations and Functions
Definition--Functions and Relations Concepts--Discrete Functions	Discrete Functions Topic Functions and Relations Definition Discrete functions are functions that are defined only for a set of discrete points.	Special Functions
Definition--Functions and Relations Concepts--Distorting a Function Horizontally	Distorting a Function Horizontally Topic Functions and Relations Definition Distorting a function horizontally involves stretching or compressing the graph of the function along the x-axis. Description Horizontal distortions of functions are significant because they alter the input values while maintaining the overall shape of the graph. This is mathematically represented as f(kx) where k is a constant. If k > 1, the function compresses horizontally, and if 0 < 𝑘 < 1, it stretches.	Relations and Functions
Definition--Functions and Relations Concepts--Distorting a Function Vertically	Distorting a Function Vertically Topic Functions and Relations Definition Distorting a function vertically involves stretching or compressing the graph of the function along the y-axis. Description Vertical distortions of functions are significant because they alter the output values while maintaining the overall shape of the graph. This is mathematically represented as kf(x)	Relations and Functions
Definition--Functions and Relations Concepts--Domain of a Function	Domain of a Function Topic Functions and Relations Definition The domain of a function is the set of all possible input values (x-values) for which the function is defined.	Relations and Functions
Definition--Functions and Relations Concepts--Even Function	Even Function Topic Functions and Relations Definition An even function is a function that satisfies the condition f(x) = f(−x) for all x in its domain. Description Even functions are important in mathematics because they exhibit symmetry about the y-axis. This property is useful in various fields, including physics and engineering, where symmetry simplifies analysis and problem-solving. For example, the function f(x)=x2	Relations and Functions
Definition--Functions and Relations Concepts--Function	Function Topic Functions and Relations Definition A function is a relation that uniquely associates each element of a set with exactly one element of another set.	Relations and Functions
Definition--Functions and Relations Concepts--Function Machine	Function Machine Topic Functions and Relations Definition A function machine is a conceptual tool used to understand how functions work by visualizing inputs and outputs. Description The function machine is a useful educational tool that helps students grasp the concept of functions by visualizing the process of converting inputs into outputs. It emphasizes the idea that a function takes an input, processes it according to a specific rule, and produces an output. For example, if the function is f(x) = x + 2	Relations and Functions
Definition--Functions and Relations Concepts--Function Notation	Function Notation Topic Functions and Relations Definition Function notation is a way to represent functions in the form f(x), where f denotes the function and x denotes the input variable. Description Function notation is a standardized way to write functions, making it easier to understand and communicate mathematical relationships. It is widely used in algebra, calculus, and other branches of mathematics. For example, the notation f(x) = x2	Relations and Functions
Definition--Functions and Relations Concepts--Function Table	Function Table Topic Functions and Relations Definition A function table is a table that lists input values and their corresponding output values for a given function. Description Function tables are useful tools in mathematics for organizing and analyzing the relationship between inputs and outputs of a function. They help in visualizing how a function behaves and in identifying patterns. For example, a function table for f(x) = 2x + 1	Relations and Functions
Definition--Functions and Relations Concepts--Graphs of Functions	Graphs of Functions Topic Functions and Relations Definition Graphs of functions are visual representations of the relationship between input values and output values of a function. Description Graphs of functions are essential tools in mathematics for visualizing how a function behaves. They provide a clear picture of the relationship between the input and output values, making it easier to analyze and interpret the function. For example, the graph of f(x) = x2	Relations and Functions
Definition--Functions and Relations Concepts--Graphs of Relations	Graphs of Relations Topic Functions and Relations Definition Graphs of relations are visual representations of the relationship between two sets of values, not necessarily functions.	Relations and Functions
Definition--Functions and Relations Concepts--Increasing Function	Increasing Function Topic Functions and Relations Definition An increasing function is a function where the value of the function increases as the input increases.	Relations and Functions
Definition--Functions and Relations Concepts--Independent Variable	Independent Variable Topic Functions and Relations Definition An independent variable is a variable that represents the input or cause and is manipulated to observe its effect on the dependent variable.	Relations and Functions
Definition--Functions and Relations Concepts--Inverse Function	Inverse Function Topic Functions and Relations Definition An inverse function is a function that reverses the effect of the original function, such that f(f−1(x)) = x.	Functions and Their Inverses
Definition--Functions and Relations Concepts--Odd Function	Odd Function Topic Functions and Relations Definition An odd function is a function that satisfies the condition f(−x) = −f(x) for all x in its domain.	Relations and Functions
Definition--Functions and Relations Concepts--Parametric Equations	Parametric Equations Topic Functions and Relations Definition Parametric equations are a set of equations that express the coordinates of the points of a curve as functions of a variable called a parameter.	Relations and Functions
Definition--Functions and Relations Concepts--Piecewise Functions	Piecewise Functions Topic Functions and Relations Definition Piecewise functions are functions defined by multiple sub-functions, each applying to a certain interval of the domain.	Special Functions
Definition--Functions and Relations Concepts--Range of a Function	Range of a Function Topic Functions and Relations Definition The range of a function is the set of all possible output values (y-values) that the function can produce. Description Understanding the range of a function is crucial in mathematics because it defines the scope of possible outputs. The range is determined by the function's rule and the domain. For example, the range of the function f(x) = x2	Relations and Functions
Definition--Functions and Relations Concepts--Recursive Function	Recursive Function Topic Functions and Relations Definition A recursive function is a function that calls itself in its definition. Description Recursive functions are important in mathematics and computer science because they provide a way to solve problems by breaking them down into simpler sub-problems. They are defined by a base case and a recursive case. For example, the factorial function f(n) = n⋅f(n−1) with f(0)=1	Relations and Functions
Definition--Functions and Relations Concepts--Reflecting a Function	Reflecting a Function Topic Functions and Relations Definition Reflecting a function involves flipping the graph of the function over a specified axis. Description Reflecting functions is significant in mathematics because it helps in understanding the symmetry and transformations of functions. A function can be reflected over the x-axis or y-axis, changing its orientation. For example, reflecting the function f(x) = x2	Relations and Functions
Definition--Functions and Relations Concepts--Relation	Relation Topic Functions and Relations Definition A relation is a set of ordered pairs, where each element from one set is paired with an element from another set.	Relations and Functions
Definition--Functions and Relations Concepts--Step Function	Step Function Topic Functions and Relations Definition A step function is a function that increases or decreases abruptly at certain points, creating a series of steps.	Special Functions
Definition--Functions and Relations Concepts--Translating a Function	Translating a Function Topic Functions and Relations Definition Translating a function involves shifting the graph of the function horizontally, vertically, or both, without changing its shape. Description Translating functions is significant in mathematics because it helps in understanding how functions behave under shifts. A function can be translated horizontally by adding or subtracting a constant to the input, and vertically by adding or subtracting a constant to the output. For example, translating the function f(x) = x2 horizontally by 2 units results in	Relations and Functions
Definition--Functions and Relations Concepts--Vertical Line Test	Vertical Line Test Topic Functions and Relations Definition The vertical line test is a method used to determine if a graph represents a function by checking if any vertical line intersects the graph more than once. Description The vertical line test is important in mathematics because it helps in identifying whether a given graph represents a function. If a vertical line intersects the graph at more than one point, then the graph does not represent a function. This test is used in various fields, including computer science for validating functions in programming and in mathematics for analyzing graphs. For example, the graph of	Relations and Functions
Definition--Functions and Relations Concepts--Visual Models of Functions	Visual Models of Functions Topic Functions and Relations Definition Visual models of functions are graphical representations that illustrate the relationship between input and output values of functions. Description Visual models of functions are important in mathematics because they provide a clear and intuitive way to understand how functions behave. These models include graphs, tables, and diagrams that show the relationship between input and output values. For example, the graph of f(x) = x2	Relations and Functions
Definition--Functions and Relations Concepts--Visual Models of Relations	Visual Models of Relations Topic Functions and Relations Definition Visual models of relations are graphical representations that illustrate the relationship between two sets of values, not necessarily functions.	Relations and Functions
Definition--Functions and Relations Concepts--Visualization of the Dependent Variable	Visualization of the Dependent Variable Topic Functions and Relations Definition Visualization of the dependent variable involves graphically representing the outcomes or responses that depend on the independent variable.	Relations and Functions
Definition--Functions and Relations Concepts--Visualization of the Independent Variable	Visualization of the Independent Variable Topic Functions and Relations Definition Visualization of the independent variable involves graphically representing the variable that is manipulated to observe its effect on the dependent variable.	Relations and Functions
Geometry Applications Teachers Guide: 3D Geometry	Geometry Applications Teachers Guide: 3D Geometry This is the Teacher's Guide that accompanies Geometry Applications: 3D Geometry. This is part of a collection of teacher's guides. To see the complete collection of teacher's guides, click on this link. Note: The download is a PDF file. Related Resources To see resources related to this topic click on the Related Resources tab above.	Applications of 3D Geometry
Google Earth Voyager Story: The Geometry of Sustainable Architecture, Part 2	Google Earth Voyager Story: The Geometry of Sustainable Architecture, Part 2 Topic Geometric Models	Surface Area, Volume and Rational Functions and Equations
Google Earth Voyager Story: The Mathematics of Pyramids, Part 1	Google Earth Voyager Story: The Mathematics of Pyramids, Part 1 Topic Geometric Models	Pyramids
Google Earth Voyager Story: The Mathematics of Pyramids, Part 2	Google Earth Voyager Story: The Mathematics of Pyramids, Part 2 Topic Geometric Models	Pyramids
INSTRUCTIONAL RESOURCE: Algebra Application: Creating an Exercise Chart	INSTRUCTIONAL RESOURCE: Algebra Application: Creating an Exercise Chart In this Algebra Application, students develop a linear mathematical model based on the maximum heart rate during exercise based on age. Using this model, students investigate heart rate for moderate and vigorous workouts. The math topics covered include: Mathematical modeling, Linear functions, Families of functions, Computational thinking. The culminating activity is for students to create a simple program (using either a spreadsheet or a programming language like Python) to develop an exercise chart. This is a great back-to-school activity for middle school or high school students. A relevant real-world application allows them to review math concepts.	Applications of Linear Functions and Slope-Intercept Form
INSTRUCTIONAL RESOURCE: Algebra Application: Linear Functions: Circumference vs. Diameter	INSTRUCTIONAL RESOURCE: Algebra Application: Linear Functions: Circumference vs. Diameter In this Algebra Application, students study the direction between diameter and circumference of a circle. Through measurement and data gathering students analyze the line of best fit and explore ways of calculating pi. The math topics covered include: Mathematical modeling, Linear functions, Data gathering and analysis, Ratios, Direct variation. This is a great back-to-school activity for middle school or high school students. This is also a great crossover activity that ties algebra and geometry.	Applications of Linear Functions, Applications of Ratios, Proportions, and Percents and Applications of Circles
INSTRUCTIONAL RESOURCE: Tutorial: Analyzing Graphs of Quadratic Functions in Factored Form	INSTRUCTIONAL RESOURCE: Tutorial: Analyzing Graphs of Quadratic Functions in Factored Form This slide show provides 8 examples of quadratic functions in factored form and analyzes their graphs. This is part of a collection of tutorials on a variety of math topics. To see the complete collection of these resources, click on this link. Note: The download is a PPT file. Library of Instructional Resources To see the complete library of Instructional Resources , click on this link.	Quadratic Equations and Functions