Question

Factor x^2 + 9x = -20​

Answer 1

see below

Explanation:

x^2 + 9x = -20​

x^2 + 9x + 20 = 0

factor the expression

(x + a)(x + b)

a + b = 9

a = 4

b = 5

ab = 20

rewrite the factor expression:

(x + 4) (x + 5)

x + 4 = 0 and x + 5 = 0

therefore,

x = -4

x = -5

Answer 2

(x +5) (x +4) = 0

Explanation:

x^2 + 9x +20 = 0

x^2 + 4x + 5x +20 = 0

x(x + 4) + 5(x + 4) = 0

(x +5) (x +4) = 0