Question

Can someone help me thanks

Answer 1

Answer:

-142

Step-by-step explanation:

So we have the function:

$f(x)=-x^2-9x+20$

To find f(9), substitute x for 9:

$f(9)=-(9)^2-9(9)+20$

Square the first term and multiply the second:

$f(9)=-81-81+20$

Add:

$f(9)=-142$

And that's our answer :)

Answer 2

f(x)=-x^2-9x+20
f(9)=-(9)^2-9(9)+20
f(9)=-81-81+20
f(9)=-142