The fence you have must fit the perimeter of the rectangle.
With 36 feet of fence, these are the rectangles that you can enclose:
1-ft x 17-ft . . . Area = 17 ft²
2 x 16 . . . Area = 32 ft²
3 x 15 . . . Area = 45 ft²
4 x 14 . . . Area = 56 ft²
5 x 13 . . . Area = 65 ft²
6 x 12 . . . Area = 72 ft²
7 x 11 . . . Area = 77 ft²
8 x 10 . . . Area = 80 ft²
9 x 9 . . . Area = 81 ft²
