Question

If f(x) = −-4x^{2} + 15, then f(−3) =

Answer 1

Answer:

$\Huge \boxed{-21}$

Step-by-step explanation:

$f(x) = -4x^{2} + 15$

f(-3), the input is -3 for the function f(x).

The value of x  =  -3

$f(-3) = -4(-3)^{2} + 15$

Evaluate the expression.

$f(-3) = -4(9)+ 15$

$f(-3) = -36+ 15$

$f(-3)=-21$

The value of f(-3) is -21.

Answer 2

Answer:

f(-3) = -21

Step-by-step explanation:

To find f(-3), we just need to plug x = -3 into f(x) so:

f(-3) = -4 * (-3)² + 15

= -4 * 9 + 15 = -36 + 15 = -21