Solve the LP problem. If no optimal solution exists, indicate whether the feasible region is empty or the objective function is unbounded. HINT [See Example 1.] (Enter EMPTY if the region is empty. Enter UNBOUNDED if the function is unbounded. ) Minimize c = x + y subject to x + 7y28 7x + yz8 x 2 0, y 2 0. C = ( x, y ) =