what are the vertices if the feasible region with constraints 2 x + 10 ≥ y , 4 x + 2 ≤ y , x ≥ 0 , y ≥ 0 2 x + 10 ≥ y , 4 x + 2 ≤ y , x ≥ 0 , y ≥ 0