Question

Complete the square to solve the following quadratic equation: x2+2x−8=0
.(1 point)

x=−2
, x=4


x=2
, x=−4


x=−10
, x=8


x=10
, x=−8

Answer 1

x^2 + 2x − 8 = 0
x^2 + 2x = 8
Add 1 (since (2/2)^2 = 1) to both sides:
x^2 + 2x + 1 = 9
(x + 1)^2 = 9
x + 1 = ±3 → x = -1 ± 3

So x = 2 or x = −4.