f(x)=x^2
f(x+1)=(x+1)^2
(x+3)^2=(x+1)^2
x^2+6x+9=x^2+2x+1
4x=-8
x=-2
(x+1)^2=(x+3)^2
x^2+2x+1=x^2+6x+9
f(x)=x^2
f(x+1)=(x+1)^2
(x+3)^2=(x+1)^2
x^2+6x+9=x^2+2x+1
4x=-8
x=-2
(x+1)^2=(x+3)^2
x^2+2x+1=x^2+6x+9
4x=-8
x=-2