A rectangular photograph is surrounded by a border that is 1 inch wide on each side. The total area of the photograph and the border is M square inches. If the border had been 3 inches wide on each side, the total area would have been (M + 64) square inches. What is the perimeter of the photograph, in inches?
Choose the correct choice:
A) 16
B) 24
C) 32
D) 40
E) 48
Let x and y be the width and length of the photograph.   (x+2)(y+2)=M and so (1) xy + 2x + 2y + 4 = M   (x+6)(y+6)=M and so (2) xy + 6x + 6y + 36 = M+64   Let's subtract equation (1) from equation (2).   4x + 4y + 32 = 64   2x + 2y = 16, which is the perimeter of the photograph.   The answer is 16.
<result>A</result>
A rectangular photograph is surrounded by a border that is 1 inch wide on each side. The total area of the photograph and the border is M square inches. If the border had been 3 inches wide on each side, the total area would have been (M + 64) square inches. What is the perimeter of the photograph, in inches?