Let
be the short, medium and long side, respectively. If we translate all the information into formulas, we get the following system:

Using the second equation, we can express the middle side in terms of the small one, and reduce the system to two equations in two unknowns:

And thus

But then again, using the first equation, the third becomes

So, the longest side is 12. Since the small is half the long, we have
. Finally, the medium is three more of the small, so we have
