SOLUTION: Given f(x)=-x^2-4x+7; g(x)=3-x, find (fog)(-3)

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Question 737041: Given f(x)=-x^2-4x+7; g(x)=3-x, find (fog)(-3)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

(gof)(x) means g%28f%28x%29%29, so you substitute the f%28x%29 into the g formula

g%28x%29+=+3-x
g%28f%28x%29%29=3-%28f%28x%29%29
g%28f%28x%29%29=3-%28-x%5E2-4x%2B7%29
g%28f%28x%29%29=3%2Bx%5E2%2B4x-7
g%28f%28x%29%29=x%5E2%2B4x-4.....plug in x=-3 to find %28fog%29%28-3%29
fog=%28-3%29%5E2%2B4%28-3%29-4
fog=9-12-4
fog=9-16
fog=-7