In the following exercises, evaluate the integral using area formulas. 76.
\int_0^3 (3-x)dx77.
\int_2^3 (3-x)dx78.
\int_(-3)^3 (3-|x|)dx79.
\int_0^6 (3-|x-3|)dx80.
\int_(-2)^2 \sqrt(4-x^(2))dx81.
\int_1^5 \sqrt(4-(x-3)^(2))dx82.
\int_0^(12) \sqrt(36-(x-6)^(2))dx