In geometry, the elongated square pyramid is one of the Johnson solids (). As the name suggests, it can be constructed by elongating a square pyramid () by attaching a cube to its square base. Like any elongated pyramid, it is topologically (but not geometrically) self-dual. Formulae The following formulae for the height (), surface area () and volume () can be used if all faces are regular, with edge length : Dual polyhedron The dual of the elongated square pyramid has 9 faces: 4 triangular, 1 square and 4 trapezoidal. Related polyhedra and honeycombs The elongated square pyramid can form a tessellation of space with tetrahedra, similar to a modified tetrahedral-octahedral honeycomb. See also Elongated square bipyramid References External links Johnson solids Self-dual polyhedra Pyramids and bipyramids