Let's take a look at the difference of squares of odd numbers:
$$11^2 - 5^2=96$$
$$5^2 - 3^2=16$$
Find the difference of some more squares of odd numbers.
What do you notice about your answers?
Can you prove your conjecture?
You can find some hints on how to construct a proof in the Getting Started section.
Other questions to think about:
Once you have had a think about this problem, you might like to think about these questions.