Formula: 0.5*(n2-3n) where n is the number of sides
3
six
It has: 0.5*(100^2-(3*100)) = 4850 diagonals
There is no such shape. And unfortunately the word is too much like two terms to determine which of them you mean.If the polygon has n sides (n>3), then it has n*(n-3)/2 diagonals.
You approximate the irregular shape with many small regular figure, for example, long and thin rectangles.
a triangle has 0 diagnols
8
2
2
35
44
None
10 figure we make from cylindrical shape
A polygon with n sides has n*(n-3)/2 diagonals (not diagnols!).So, an octagon has 8*5/2 = 20 of them.
3
six
That will depend on the shape of the figure which isn't named