N art museum has a pentagon-shaped room. When drawn to scale on a coordinate grid, the corners of the room are points A(18,24) ; B(9,24) ; C(9,10) ; D(16,8) ; E(22,16), shown in feet. The walls are 9 feet high. The museum is going to paint four of the walls: , , , and . Assume one gallon of paint is enough to cover 488 square feet.

How many gallons of paint should the museum purchase? Enter your answer as a whole number.