SOLUTION: Given f(x) = 5x2 – 3x + 1, find f(–2).

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Given f(x) = 5x2 – 3x + 1, find f(–2).      Log On


   



Question 113983: Given f(x) = 5x2 – 3x + 1, find f(–2).
Found 2 solutions by checkley71, jim_thompson5910:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
F(-2)=5*(-2)^2-3*(-2)+1
F(-2)=5*4+6+1
F(-2)=20+7
F(-2)=27 ANSWER.

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

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