Chapter 14.2, Problem 12E

Evaluating a Double Integral In Exercises 7-12, sketch the region R and evaluate the iterated integral ${\displaystyle \int {}_R}{\displaystyle \int f(x,y)dA}$.

${\displaystyle {\int }_0^1{\displaystyle {\int }_{y-1}^0{e}^{x+y}+{\displaystyle {\int }_0^1{\displaystyle {\int }_0^{1-y}{e}^{x+y}}}dxdy}}$