SOLUTION: Could you help me solve this problem? Find and simplify where possible. f(x)= x squared -5 if x is 2f (-3)

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Question 12246: Could you help me solve this problem?
Find and simplify where possible.
f(x)= x squared -5 if x is 2f (-3)

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29+=+x%5E2+-+5

First find f(-3), which means to substitute the value of x=-3 into the given formula:
f%28x%29+=+x%5E2+-+5
f%28-3%29+=+%28-3%29%5E2+-+5 = 9-5 = 4

Next, find 2f(-3) which just means to take f(-3) and multiply it times 2.
2f(-3) = 2*4 = 8

R^2 at SCC