Difference between revisions of "Icosahedron"

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An '''icosahedron''' is any [[polyhedron]] with twenty [[face]]s.  In fact, the term is almost always used to refer specifically to a polyhedron with twenty [[triangle | triangular]] faces, and modifying words or alternate terminology are used to refer to other twenty-sided polyhedra, as in the case of the [[rhombic icosahedron]].
 
An '''icosahedron''' is any [[polyhedron]] with twenty [[face]]s.  In fact, the term is almost always used to refer specifically to a polyhedron with twenty [[triangle | triangular]] faces, and modifying words or alternate terminology are used to refer to other twenty-sided polyhedra, as in the case of the [[rhombic icosahedron]].
  
The [[regular icosahedron]] is one of the five [[Platonic solid]]s: its faces are all [[equilateral]] [[triangle]]s.  It has twenty [[vertex | vertices]] and thirty [[edge]]s.  Five faces meet at each vertex.  It is [[Platonic_Solid#Duality | dual]] to the [[regular dodecahedron]].
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The [[regular icosahedron]] is one of the five [[Platonic solid]]s: its faces are all [[equilateral]] [[triangle]]s.  It has twenty [[vertex | vertices]] and thirty [[edge]]s.  Five faces meet at each vertex.  It is [[Platonic_solid#Duality | dual]] to the [[regular dodecahedron]].
  
 
A soccer ball is an example of an icosahedron with the vertices flattened into pentagonal faces.  
 
A soccer ball is an example of an icosahedron with the vertices flattened into pentagonal faces.  

Latest revision as of 12:01, 25 August 2019

An icosahedron is any polyhedron with twenty faces. In fact, the term is almost always used to refer specifically to a polyhedron with twenty triangular faces, and modifying words or alternate terminology are used to refer to other twenty-sided polyhedra, as in the case of the rhombic icosahedron.

The regular icosahedron is one of the five Platonic solids: its faces are all equilateral triangles. It has twenty vertices and thirty edges. Five faces meet at each vertex. It is dual to the regular dodecahedron.

A soccer ball is an example of an icosahedron with the vertices flattened into pentagonal faces.

See Also

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