Decagon

Regular decagon
A regular decagon
TypeRegular polygon
Edges and vertices10
Schläfli symbol{10}, t{5}
Coxeter–Dynkin diagrams
Symmetry groupDihedral (D10), order 2×10
Internal angle (degrees)144°
PropertiesConvex, cyclic, equilateral, isogonal, isotoxal
Dual polygonSelf

In geometry, a decagon (from the Greek δέκα déka and γωνία gonía, "ten angles") is a ten-sided polygon or 10-gon.[1] The total sum of the interior angles of a simple decagon is 1440°.

  1. ^ Sidebotham, Thomas H. (2003), The A to Z of Mathematics: A Basic Guide, John Wiley & Sons, p. 146, ISBN 9780471461630.