SOLUTION: find (fog)(-2) when g(x)=2x-1, f(x)=2x^2+3x-4 I need help.

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Question 952691: find (fog)(-2) when g(x)=2x-1, f(x)=2x^2+3x-4
I need help.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
First find g(-2).
g%28-2%29=2%28-2%29-1
g%28-2%29=-4-1
g%28-2%29=-5
So then,
f%28g%28-2%29%29=f%28-5%29
f%28g%28-2%29%29=2%28-5%29%5E2%2B3%28-5%29-4
f%28g%28-2%29%29=2%2825%29%2B%28-15%29-4
f%28g%28-2%29%29=50-15-4
f%28g%28-2%29%29=31