Respuesta :

choixongdong
(f+g)(x) = x^2 -2x +6x + 4
(f+g)(x) = x^2 + 4x + 4
(f+g)(x) = (x + 2)^2

(x + 2)^2 = 0
x + 2 = 0
x = -2

answer
B. -2