What are the solutions of the equation x 22 2x 2 15 0 U

What are the solutions of the equation (x + 2)^2 – 2(x + 2) – 15 = 0? Use u substitution to solve

x = –7 and x = 1

x = –5 and x = 3

x = –3 and x = 5

x = –1 and x = 7

Given (x + 2)^2 – 2(x + 2) – 15 = 0

put y = x + 2

then y^2 – 2y – 15 = 0

(y - 5)(y + 3) = 0

then y = 5 or -3.

for y = x + 2 = 5 ==> x = 5-2=3

and y = x + 2 = -3 ==> x = -3-2=-5

then x = –5 and x = 3.