## Algebra 1

Substitute the given values and simplify. $(3c^2-3d)^2-21$ $=(3(3^2)-3(5))^2-21$ simplify the exponent in parentheses $=(3(9)-3(5))^2-21$ multiply in parentheses $=(27-15)^2-21$ subtract in parentheses $=12^2-21$ solve exponent $=144-21$ subtract $=123$