SOLUTION: Let f(x)=8+5x−x^2. Find the difference quotient f(8+h)−f(8)/h. I have no idea how to solve this. Thanks in advance

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Question 1144618: Let f(x)=8+5x−x^2. Find the difference quotient f(8+h)−f(8)/h.
I have no idea how to solve this. Thanks in advance
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Let f(x)=8+5x−x^2. )the difference quotient f(8+h)−f(8)/h.
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It it's %28f%288%2Bh%29-f%288%29%29%2Fh
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find f(8+h)
Wherever there's x, replace it with 8+h
f(8+h) = 8 + 40+5h -(64+16h+h^2) = -h^2 -11h - 16
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Find f(8)
f(8) = 8+40-64 = -16
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Subtract
f(8+h)−f(8) = -h^2 - 11h
Divide by h
---> -h - 11