If you are only considering sides that are whole numbers, then you're basically looking for all the possible ways to multiply two numbers to get 48. In other words, we're listing all the ways to factor 48.
That list is
The order for each pairing doesn't matter. Something like 3*16 is the same as 16*3.
If x and y were not positive integers, but instead positive real numbers, then x*y = 48 has infinitely many (x,y) solutions.
