9. Consider constraint inequalities: 2x + y 1 x+3y1 Make a sketch of the feasible set. For x0, y 0 each of the following objective functions, optimize said function and find the point(s) where the function is optimized (if it exists). (a) minimize f(x, y) = x+y (b) minimize f(x, y) = -x-y (c) minimize f(x, y) = x (d) maximize f(x, y) = max(x,y} (e) maximize f(x, y) = x + 9y