The perimeter of a rectangle is 20 cm. If its length and width are in whole centimeters, how many possible values of the area of the rectangle?

The perimeter of a rectangle is 20 cm. If its length and width are in whole centimeters, how many possible values of the area of the rectangle?

Length + width = 10 cm, and they are all whole centimeters
a=9,b=1,s=9
a=8,b=2,s=16
a=7,b=3,s=21
a=6,b=4,s=24
A is not equal to B, so there are four possibilities