How many rectangles with different shapes?

The perimeter of a rectangle is 20 feet and the foot-measure of each side is a whole number. How many rectangles with different shapes satisfy these conditions?

The perimeter of a rectangle = 2 (l+b) = 20 feet
=> l+b = 10 feet.

As the sides of the rectangle are whole numbers, the possible values for the sides based on the above condition are 1 by 9, 2 by 8, 3 by 7, 4 by 6, and 5 by 5.

There are 5 different rectangles for the given conditions.