In the following exercises, evaluate the integral using area formulas. 76.
\int_0^3 (3-x)dx
77.
\int_2^3 (3-x)dx
78.
\int_(-3)^3 (3-|x|)dx
79.
\int_0^6 (3-|x-3|)dx
80.
\int_(-2)^2 \sqrt(4-x^(2))dx
81.
\int_1^5 \sqrt(4-(x-3)^(2))dx
82.
\int_0^(12) \sqrt(36-(x-6)^(2))dx