Question 400993: f(x) = 5x^2 - 7x + 9; f(-4) = ?
Answer by rapaljer(4671)   (Show Source):
You can put this solution on YOUR website! You need to substitute the value of x=-4 in place of all the x's as in the following solution.
f(x) = 5x^2 -7x + 9
f(-4)=5(-4)^2-7(-4) + 9
= 5*16+28+9
= 80 +28 + 9
=117
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Dr, Robert J. Rapalje, Retired
Seminole State College of Florida
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