MA19.8.9

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

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.

Vocabulary

Slope
Rate of change
Initial Value
Y-intercept

Aligned Learning Resources

ELA | Lesson 2 | Comparing and Contrasting Texts

Graphville Shopping Excursion

Design by Adaptive Theme