Hey CInsbstnkng!
The number of diagonals of a polygon can be defined as \(d = \frac{n(n-3)}{2}\) where n is the number of sides (for any amount of sides over 3)
so then you can form an equation like so:
\(2n = \frac{n(n-3)}{2}\)
this sets 2 times the sides (n) against the number of diagonals.
Hope this helps!
(If you are interested in how to find the diagonal formula you can look here https://byjus.com/diagonal-of-polygon-formula)
