SOLUTION: if f(x)=2x²-3x+5, find f(2a-5)+5f(-a)

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Question 1177135: if f(x)=2x²-3x+5, find f(2a-5)+5f(-a)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

f%28x%29=2x%5E2-3x%2B5
find
f%282a-5%29%2B5f%28-a%29
first find f%282a-5%29

f%282a-5%29=2%282a-5%29%5E2-3%282a-5%29%2B5
f%282a-5%29=2%284a%5E2-20a%2B25%29-6a%2B15%2B5
f%282a-5%29=8a%5E2-40a%2B50-6a%2B20
f%282a-5%29=8a%5E2-46a%2B70

now find 5f%28-a%29
5f%28-a%29=5%282%28-a%29%5E2-3%28-a%29%2B5%29
5f%28-a%29=5%282a%5E2%2B3a%2B5%29
5f%28-a%29=10a%5E2%2B15a%2B25
then

f%282a-5%29%2B5f%28-a%29=8a%5E2-46a%2B70%2B10a%5E2%2B15a%2B25
f%282a-5%29%2B5f%28-a%29=18a%5E2-31a%2B95