The functions Area, InscribedRadius, and CircumscribedRadius give information for a polygon with edges of length 1. The list of coordinates returned by Vertices is conventional for the specified polygon and does not necessarily correspond to a polygon with unit edge length.
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An octagon has 8 edges.
This is the area of an octagon when the length of each edge is 1.
These points represent the coordinates of the vertices of an octagon.