Regular icosagon
A regular icosagon.
Edges and vertices	20
Schläfli symbol	{20}
Coxeter–Dynkin diagram	Image:CDW 20.png
Symmetry group	Dihedral (D20)
Area (with t=edge length)
Internal angle (degrees)	162°

In geometry, an icosagon is a twenty-sided polygon. The sum of any icosagon's interior angles is 3240 degrees. It is a regular polygon, meaning all of the line segments have to be the same legnth. The swastika is considered to be an irregular icosagon^[1][2] Image File history File links Icosagon. ... An edge between two vertices For edge in graph theory, see Edge (graph theory) In geometry, an edge is a one-dimensional line segment joining two zero-dimensional vertices in a polytope. ... In geometry, a vertex (plural vertices) is a special kind of point, usually a corner of a polygon, polyhedron, or higher dimensional polytope. ... In mathematics, the Schläfli symbol is a notation of the form {p,q,r,...} that defines regular polytopes and tessellations. ... Coxeter groups in the plane with equivalent diagrams. ... Image File history File links CDW_ring. ... Image File history File links CDW_dot. ... The symmetry group of an object (e. ... This article deals with three infinite series of point groups in three dimensions which have a symmetry group which as abstract group is a dihedral group Dihn ( n ≥ 2 ). See also point groups in two dimensions. ... This article is about the physical quantity. ... External angles law In geometry, an interior angle (or internal angle) is an angle formed by two sides of a simple polygon that share an endpoint, namely, the angle on the inner side of the polygon. ... This article describes the unit of angle. ... For other uses, see Geometry (disambiguation). ... Look up polygon in Wiktionary, the free dictionary. ... This article is about the symbol. ...

References

External links

• Eric W. Weisstein, Icosagon at MathWorld.

It has been suggested that this article or section be merged with Polygons. (Discuss)

They are regular polygons Eric W. Weisstein (born March 18, 1969, in Bloomington, Indiana) is an encyclopedist who created and maintains MathWorld and Eric Weissteins World of Science (ScienceWorld). ... MathWorld is an online mathematics reference work, sponsored by Wolfram Research Inc. ... Image File history File links Merge-arrows. ... A polygon (from the Greek poly, for many, and gonos, for angle) is a closed planar path composed of a finite number of sequential straight line segments. ... Look up polygon in Wiktionary, the free dictionary. ... In geometry a henagon (or monogon) is a polygon with one side and one vertex. ... In geometry a digon is a polygon with two sides and two vertices. ... For other uses, see Triangle (disambiguation). ... This article is about the geometric shape. ... Look up pentagon in Wiktionary, the free dictionary. ... For other uses, see Hexagon (disambiguation). ... In geometry, a heptagon is a polygon with seven sides and seven angles. ... For other uses, see Octagon (disambiguation). ... In geometry, an enneagon or nonagon is a nine-sided polygon. ... a regular decagon In geometry, a decagon is any polygon with ten sides and ten angles, and usually refers to a regular decagon, having all sides of equal length and all angles equal to 144°, therefore making each angle of a regular decagon be 144°. Its Schläfli symbol is... Categories: Math stubs | Polygons ... A regular dodecagon. ... A regular triskaidecagon. ... Look up Polygon in Wiktionary, the free dictionary. ... In geometry, a pentadecagon is any 15-sided, 15-angled, polygon. ... HELLLOOOOO THERE ... Erchingers heptadecagon In geometry, a heptadecagon (or 17-gon) is a seventeen-sided polygon. ... An octadecagon is a polygon with 18 sides and 18 vertexes. ... An enneadecagon. ... A whole chiliagon is not visually discernible from a circle. ... This article or section does not cite its references or sources. ...

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