Question

Find the maximum and minimum values of f(x, y) =8x+y for the polygonal convex set having vertices at (0, 0), (4, 0), (3, 5), (0, 5).

Answer 1

Does the max or min's occur at the vertices?
If so then just plug in the points into f(x,y)

Answer 2

that is evaluate
f(0,0)
f(4,0)
f(3,5)
f(0,5)