All lessons › Unit 3 · Lines and linear functions

Inequalities in two variables

An inequality like y > 2x + 1 does not have just one answer. Its answers fill a whole region of the graph. The Digital SAT Math section often asks which point is in the solution region, or gives a word problem with a system of inequalities.

This lesson shows how to tell a solid line from a dashed line, which side to shade and how to test a point. Every step is animated, the quiz comes right after the part, and there are practice questions to build speed.

In this lesson

• Inequalities in two variables