The formula we want to use is a^{2} + b^{2} = c^{2}
c is the longest side, or the hypotenuse while a and b are the shorter sides.
So, we have a^{2} + 48^{2} = 73^{2}
That gets us a^{2} + 2304 = 5329
Subtract 2304 on each side and we get a^{2} = 3025
Now we need to take the square root of each side, which gives us a final answer of a = 55mm
