Solving Quadratic Inequalities with a Sign Graph
We summarize the strategy for solving a quadratic inequality as follows.
Strategy for Solving a Quadratic Inequality
with a Sign Graph
1. Write the inequality with 0 on the right.
2. Factor the quadratic polynomial on the left.
3. Make a sign graph showing where each factor is positive, negative, or zero.
4. Use the rules for multiplying signed numbers to determine which regions
satisfy the original inequality.