A diagonal of a polyhedron is a line segment connecting two non-adajcent vertices. How many diagaonals does a pentagonal prism have?
This might be wrong
Each vertice can connect to 6 points.
There are 5 * 2 = 10 vertices in the diagram.
so 6 * 10 = 60.
We overcounted each twice.
so
60 / 2 = 30????