Lesson 32: Solving Quadratic Equations by Factoring
Quadratic equations are equations of the form ax² + bx + c = 0. One of the most common methods for solving them is factoring.
Steps to Solve by Factoring
- Write the quadratic equation in standard form (ax² + bx + c = 0).
- Factor the quadratic completely.
- Set each factor equal to zero (Zero Product Property).
- Solve each simple equation to find the solutions.
Examples
Example 1: Solve x² + 5x + 6 = 0
- Factor: (x + 2)(x + 3) = 0
- Set each factor to zero: x + 2 = 0 or x + 3 = 0
- Solve: x = −2 or x = −3
Example 2: Solve 2x² + 7x + 3 = 0
- Factor: (2x + 1)(x + 3) = 0
- Set factors to zero: 2x + 1 = 0 or x + 3 = 0
- Solve: x = −1/2 or x = −3
Practice Problems
- Solve x² − 9x + 20 = 0
- Solve x² + 7x + 10 = 0
- Solve 3x² + 11x + 6 = 0
- Solve 4x² − 12x + 9 = 0
