x^2+30x-75

Question

Solve for x, but factor this first

Answer 1

x^2 + 30x - 75 = 0
(x^2 + 30x) - 75 = 0
(x + 15)^2 - 225 - 75 = 0
(x + 15)^2 = 300
x + 15 = sqrt(300) or = -sqrt(300)
x = -15 + sqrt(300) or x = -15 - sqrt(300)

Factorising is not advisable, since you will get:

(x - (-15 + sqrt(300)))(x - (-15 + sqrt(300))) = 0
(x + 15 - sqrt(300))(x + 15 - sqrt(300)) = 0