Standard Alignments:

TEKS Math: 8.4.C

(C) Use data from a table or graph to determine the rate of change or slope and y-intercept in mathematical and real-world problems.

CCSS Math: 8.EE.6

8.EE.6 Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b.