Question 803488
(x-1)(x+1)=(x+1)^2
x^2 -1 = x^2 +2x +1
note that using the associative property of addition we have
x^2 +2x +1 = x^2 +(2x +1), so
x^2 -1 = x^2 +(2x+1)
subtract x^2 from both sides of =
-1 = 2x +1
2x = -2
x = -1