Learning Resource Type

Classroom Resource

Manipulating Graphs

Subject Area

Mathematics

Grade(s)

7, 8

Overview

Watch how a graph is altered when key elements of the equation change. This lesson focuses on how to manipulate the equation of a line in slope intercept form to match the graphs provided deepening the understanding of both the slope and y intercept's role in the expression. This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers.

    Mathematics (2019) Grade(s): 8

    MA19.8.9

    Interpret y = mx + b as defining a linear equation whose graph is a line with m as the slope and b as the y-intercept.

    Unpacked Content

    UP:MA19.8.9

    Vocabulary

    • Slope
    • Rate of change
    • Initial Value
    • Y-intercept

    Knowledge

    Students know:
    • how to graph points on a coordinate plane.
    • Where to graph the initial value/y-intercept.
    • Understand how/why triangles are similar.
    • how to interpret y=mx equations.

    Skills

    Students are able to:
    • create a graph of linear equations in the form y = mx + b and recognize m as the slope and b as the y-intercept.
    • point out similar triangles formed between pairs of points and know that they have the same slope between any pairs of those points.
    • Show that lines may share the same slope but can have different y-intercepts.
    • Interpret a rate of change as the slope and the initial value as the y-intercept.

    Understanding

    Students understand that:
    • Slope is a graphic representation of the rate of change in linear relationships and the y-intercept is a graphic representation of an initial value in a linear relationship.
    • When given an equation in the form y = mx + b it generally symbolizes that there will be lines with varying y-intercepts. even when the slope is the same.
    • Use of the visual of right triangles created between points on a line to explain why the slope is a constant rate of change.
    Mathematics (2019) Grade(s): 8

    MA19.8.15

    Compare properties of functions represented algebraically, graphically, numerically in tables, or by verbal descriptions.

    Unpacked Content

    UP:MA19.8.15

    Vocabulary

    • Function
    • Linear
    • Non-linear
    • Slope

    Knowledge

    Students know:
    • how to find rates of change and initial values for function represented multiple ways.
    • how to graph functions when given an equation, table, or verbal description.

    Skills

    Students are able to:
    • identify the differences between functions represented in multiple contexts.
    • Tell the differences between linear and nonlinear functions.

    Understanding

    Students understand that:
    • Converting to different representations of functions can assist in their comparisons of linear functions qualitatively and quantitatively.
    Link to Resource

    CR Resource Type

    Audio/Video

    Resource Provider

    PBS
    Accessibility
    License

    License Type

    PD
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