Walks your through the various calculations for a decagon including perimeter, area, diagonal count, sum of interior angles, diagonals from a vertex, and triangles for each vertex.
Timestamps:
00:00 Intro
00:19 Decagon Shape
00:39 Perimeter of a Decagon
00:55 Area of a Decagon
01:14 Sum of Interior Angles
01:55 Number of Diagonals
02:39 Number of Diagonals from each Decagon Vertex
03:16 Number of Triangles from each Decagon Vertex
03:46 Decagon Calculator Demo