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Octagon
Polygon shape with eight sides / From Wikipedia, the free encyclopedia
"Octagonal" redirects here. For other uses, see Octagon (disambiguation) and Octagonal (disambiguation).
In geometry, an octagon (from Ancient Greek ὀκτάγωνον (oktágōnon) 'eight angles') is an eight-sided polygon or 8-gon.
Quick Facts Regular octagon, Type ...
Regular octagon | |
---|---|
![]() A regular octagon | |
Type | Regular polygon |
Edges and vertices | 8 |
Schläfli symbol | {8}, t{4} |
Coxeter–Dynkin diagrams | ![]() ![]() ![]() ![]() ![]() ![]() |
Symmetry group | Dihedral (D8), order 2×8 |
Internal angle (degrees) | 135° |
Properties | Convex, cyclic, equilateral, isogonal, isotoxal |
Dual polygon | Self |
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A regular octagon has Schläfli symbol {8} [1] and can also be constructed as a quasiregular truncated square, t{4}, which alternates two types of edges. A truncated octagon, t{8} is a hexadecagon, {16}. A 3D analog of the octagon can be the rhombicuboctahedron with the triangular faces on it like the replaced edges, if one considers the octagon to be a truncated square.