SOLUTION: Please help. Given f(x)=5x^2-3x+1 find f(-2) Thanks JMS

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Question 115524: Please help.
Given f(x)=5x^2-3x+1
find f(-2)

Thanks
JMS
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Let's evaluate f%28-2%29


f%28x%29=5x%5E2-3x%2B1 Start with the given function.


f%28-2%29=5%28-2%29%5E2-3%28-2%29%2B1 Plug in x=-2. In other words, replace each x with -2.


f%28-2%29=5%284%29-3%28-2%29%2B1 Evaluate %28-2%29%5E2 to get 4.


f%28-2%29=%2B20-3%28-2%29%2B1 Multiply 5 and 4 to get 20


f%28-2%29=%2B20%2B6%2B1 Multiply -3 and -2 to get 6


f%28-2%29=27 Now combine like terms