Well I don't no how to find it to a 2d octagon but to find it on abnormal octagon u do
8(total sides)x 6(total not attached)/2=24
Octagon
It's a 2D shape.
An octagon is a two-dimensional polygon with eight sides which can be regular or irregular
octagon
As a 2D polygon shape it is an 8 sided octagon.
octagon
Octagon
An Octagon?
An octagon
Octagon
Octagon
8 sides