Question

Solve the following quadratic equation by completing the square.

x^2 + 2x - 8 = 0

Answer 1

-4, 2

Explanation:

x² + 2x - 8 = 0

[(x + 1)² - 1] - 8 = 0

(x + 1)² - 9 = 0

(x + 1)² = 9

x + 1 = ±√9 = ±3

x = -3 - 1, +3 - 1

= -4, 2.