## Algebra 1

$9$
We rewrite the given expression as a division problem: $s^0\div r^{-2}$ The negative exponent rule states that for every nonzero number $a$ and integer $n$, $a^{-n}=\frac{1}{a^n}$. We use this rule to rewrite the expression: $s^0\div\frac{1}{r^2}$ To divide by a fraction, we multiply by the reciprocal: $s^0\times r^2$ The zero as an exponent rule states that for every nonzero number $a$, $a^0=1$. Since $s^0 = 1$ and the product of $1$ and any number is the original number, we get rid of the $s^0$ term. $r^2$ We plug in the value for $r$: $(-3)^2$ We simplify: $9$