Question

F(x) = 2x2 – 5x – 20 Find f (-9​

Answer 1

Answer:

$f( - 9) = 187$

Step-by-step explanation:

$f(x) = {2x}^{2} - 5x - 20$

To find f(-9) , substitute the value of x that's -9 into f(x). That is for every x in f (x) replace it with - 9

We have

$f( - 9) = 2 ({ - 9})^{2} - 5( - 9) - 20 \\ = 2(81) + 45 - 20 \\ = 162 + 25 \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

We have the final answer as

$f( - 9) = 187$

Hope this helps you