### Home > CAAC > Chapter 12 > Lesson 12.1.1 > Problem12-9

12-9.
1. Solve the equations and inequalities below by completing the square. Homework Help ✎

1. x2 − 2x − 3 < 0

2. x2 + 4x = 3

3. x2 + 12x + 39 > 0

4. x2 − 3x − 13.75 = 0

Solve this like an equation and then test points to find the solution region(s).

The perfect square form is (x + 1)2 = 4.

−1 ≤ x ≤ 3

$x = -2 \pm \sqrt{7}$

Refer to part (a).

The perfect square form is (x + 6)2 > −3