Question

F(x) = -4x2 + 9 Find f(-3)

Answer 1

Answer:

$f(-3)=-27$

Step-by-step explanation:

So we have the function:

$f(x)=-4x^2+9$

And we want to find f(-3).

So, let's substitute -3 for x. Thus:

$f(-3)=-4(-3)^2+9$

Square. -3 squared is positive 9:

$f(-3)=-4(9)+9$

Multiply:

$f(-3)=-36+9$

Add:

$f(-3)=-27$

And we're done!