Heptagonal prism
polyhedron with 9 faces

In geometry, the heptagonal prism is a prism with heptagonal base. This polyhedron has 9 faces (2 bases and 7 sides), 21 edges, and 14 vertices.
Area
The area of a right heptagonal prism with height
h
{\displaystyle h}
and with a side length of
L
{\displaystyle L}
and apothem
a
p
{\displaystyle a_{p}}
is given by:
A
=
7
L
⋅
(
a
p
+
h
)
{\displaystyle A=7L\cdot (a_{p}+h)}
Volume
The volume is found by taking the area of the base, with a side length of
L
{\displaystyle L}
and apothem
a
p
{\displaystyle a_{p}}
, and multiplying it by the height
h
{\displaystyle h}
, giving the formula:
V
=
7
2
⋅
h
⋅
L
⋅
a
p
{\displaystyle V={\frac {7}{2}}\cdot h\cdot L\cdot a_{p}}
This formula also works for the oblique prism due to the Cavalieri's principle.
Images
The heptagonal prism can also be seen as a tiling on a sphere:
Related polyhedra
References
External links
Weisstein, Eric W. "Prism". MathWorld.
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