F(x)=2x^(2)-5x-20 find f(-9)

Step-by-step explanation:

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

We have the final answer as

Hope this helps you

you can't solve x because it is 2 linear equation and you only have one equation