Simplify: $9-3(2^2)$ = _________.

The Rules Guiding Order of Operations require that we address exponents first, then multiplications, then subtractions.
Exponent first: $2^2=4$
$9 − 3(2^2$) = $9− 3(4)$
Multiply: $3(4) = 12$
$= 9 − 12$
Add the opposite.
$= 9 + (−12)$
Add: $9 + (−12)$
$= −3$