Evaluate the Function f(x)=-x^2-4 for x=-3

$f (x) = - x^{2} - 4$ for $x = - 3$

Replace the variable $x$ with $- 3$ in the expression.

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

Simplify the result.

Simplify each term.

Raise $- 3$ to the power of $2$ .

$f (- 3) = - 1 \cdot 9 - 4$

Multiply $- 1$ by $9$ .

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

Subtract $4$ from $- 9$ .

$f (- 3) = - 13$

The final answer is $- 13$ .

$- 13$