SOLUTION: Let f (x) = -2x2 + x -4. Evaluate f (-9).

Algebra ->  Functions -> SOLUTION: Let f (x) = -2x2 + x -4. Evaluate f (-9).      Log On


   

Question 402879: Let f (x) = -2x2 + x -4. Evaluate f (-9).
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=-2x%5E2+%2B+x+-4 Start with the given equation.


f%28-9%29=-2%28-9%29%5E2+%2B+-9+-4 Plug in x=-9.


f%28-9%29=-2%2881%29-9-4 Square -9 to get 81.


f%28-9%29=-162-9-4 Multiply -2 and 81 to get -162.


f%28-9%29=-175 Combine like terms.