Find R(3x+4y)dA\displaystyle \int\int_{{R}}{\left({3}{x}+{4}{y}\right)}{d}{A} where R\displaystyle {R} is the parallelogram with vertices (0,0), (4,-2), (-5,-1), and (-1,-3).

Use the transformation x=4u5v, y=2uv\displaystyle {x}={4}{u}-{5}{v},\ {y}=-{2}{u}-{v}