Elongated pentagonal pyramid
Encyclopedia
In geometry
, the elongated pentagonal pyramid is one of the Johnson solid
s (J9). As the name suggests, it can be constructed by elongating a pentagonal pyramid
(J2) by attaching a pentagonal prism
to its base.
The 92 Johnson solids were named and described by Norman Johnson in 1966.
Geometry
Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....
, the elongated pentagonal pyramid is one of the Johnson solid
Johnson solid
In geometry, a Johnson solid is a strictly convex polyhedron, each face of which is a regular polygon, but which is not uniform, i.e., not a Platonic solid, Archimedean solid, prism or antiprism. There is no requirement that each face must be the same polygon, or that the same polygons join around...
s (J9). As the name suggests, it can be constructed by elongating a pentagonal pyramid
Pentagonal pyramid
In geometry, a pentagonal pyramid is a pyramid with a pentagonal base upon which are erected five triangular faces that meet at a point . Like any pyramid, it is self-dual....
(J2) by attaching a pentagonal prism
Pentagonal prism
In geometry, the pentagonal prism is a prism with a pentagonal base. It is a type of heptahedron with 7 faces, 15 edges, and 10 vertices.- As a semiregular polyhedron :...
to its base.
The 92 Johnson solids were named and described by Norman Johnson in 1966.
Dual polyhedron
The dual of the elongated pentagonal pyramid has 11 faces: 5 triangular, 1 pentagonal and 5 trapezoidal.| Dual elongated pentagonal pyramid | Net of dual |
|---|---|