Grade 8 · Functions

CCSS.MATH.CONTENT.8.F.A.3

Interpret the equation y = mx + b as defining a linear function, whose graph is a straight line; give examples of functions that are not linear.

Read this standard on the official Common Core site

Lessons that teach this standard

• How to Graph Linear Equations

  Graph a line three ways — from slope-intercept form, from intercepts, or from a table — and understand why every point on the line is a solution.

• Linear vs Nonlinear Functions: How to Tell Them Apart

  Four reliable tests for deciding whether a relationship is linear — from its equation, its table, its graph, or its rate of change.

• Point-Slope Form: Writing a Line from One Point

  Learn point-slope form, why it is the slope formula rearranged, and how to use it to write a line's equation from a single point and a slope.

• Slope-Intercept Form: y = mx + b

  Understand y = mx + b, what m and b each control, how to graph a line from it in two moves, and how to rewrite any linear equation into this form.