Area = length x width. So, you can't find the actual length and width from the area because there are infinite possibilities.
But you can figure out a set of likely solutions. For example:
If A = 35 l = 1, 5, 7, 35 and w = 1, 5, 7, 35.
We now know that the length and width must be one of these 3.
Even if the area is a prime number, there are still infinite fractional possibilities.
So, there really is no way to actually find the length and width from the area.
