Decagon

In geometry, the decagon (also decagon ) is any polygon with ten sides and ten corners. Usually a regular decagon with sides of equal length and equal angles of 144 ° is meant. His Schläfli symbol is { 10}.

Formulas

Calculation of area A

The area of ​​a regular decagon with side length is calculated as follows:

Construction of a decagon

A regular decagon is constructible with compass and straightedge.