If f(x)=x+7f(x) = x + 7f(x)=x+7 and g(x)=x−7g(x) = x - 7g(x)=x−7, what is (f+g)(x)(f+g)(x)(f+g)(x)?
000
2x2x2x
141414
x2−49x^2 - 49x2−49