**Find the absolute maximum and minimum values off on the set D.**

**f(x , y) = x + y - xy, D is the closed triangular region with vertices (0, 0), (0 , 2) , and (4 , 0)**

**Answer:**

**Find the absolute maximum and minimum values off on the set D.**

**f(x , y) = x + y - xy, D is the closed triangular region with vertices (0, 0), (0 , 2) , and (4 , 0)**

**Answer:**