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Mathematics (2019) Grade(s): 7 - Grade 7 Accelerated


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


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.


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 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.


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 you will have lines with varying y-intercepts. even when the slope is the same.
  • you can use the visual of right triangles created between points on a line to explain why the slope is a constant rate of change.


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

Aligned Learning Resources