Question

I need help with functions! Given f(x)=x^2 + 2x, solve for x where f(x+2) = 0

Answer 1

(x+2)^2 + 2(x+2)
(x+2)(x+2) + (2x+4)
(x^2+4x+4) + (2x+4)
x^2 +6x + 8 = 0
factor.
(x+4)(x+2) = 0
x = -4 and -2
f(x+2) = 0 @ -4 and -2

Answer 2

oh so you just treat f(x+2) like any other number and just plug it in for x?

Answer 3

yes, just plug (x+2) anywhere you see an "x" in the function :D

Answer 4

okay haha thanks for the help!