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3 years ago

Can someone help me thanks

Mathematics

2 answers:

Helga [31]3 years ago

7 0

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 :)

Alenkasestr [34]3 years ago

5 0

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

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