posted by jacob .
Consider every whole number area from 2 square units to 30 square units. For which of these areas is there only one rectangle with whole number side lengths?
When the area is represented by a prime number
e.g. area = 11
the sides can only be 1 by 11
area = 12
sides could be 1by12 or 2by6 or 3by4
so which are the prime numbers from 2 to 30?
btw, 2 is considered a prime number.