which of the following correctly completes the square for the equation below x2+2x=19

A: (x+1)^2=23
B:(x+2)^2=20
C:(x+1)^2=20
D:(x+2)^2=23

Respuesta :

answer is C:(x+1)^2=20

x2 + 2x = 19
x2 + 2x + 1 = 19 + 1
(x + 1)^2 = 20