Illustration of a decagonal bifrustum created by three parallel planes of decagons with the middle plane largest. The top and bottom decagons are congruent. It can be constructed from two congruent frustums across a plane of symmetry, or as a bipyramid with truncated vertices.

Decagonal Bifrustum

Illustration of a decagonal bifrustum created by three parallel planes of decagons with the middle plane…

Illustration of a decagon circumscribed about a circle. This can also be described as a circle inscribed in a decagon.

Decagon Circumscribed About A Circle

Illustration of a decagon circumscribed about a circle. This can also be described as a circle inscribed…

Illustration of a decagon inscribed in a circle. This can also be described as a circle circumscribed about a decagon.

Decagon Inscribed In A Circle

Illustration of a decagon inscribed in a circle. This can also be described as a circle circumscribed…

Illustration of a 5-point star inscribed in a circle. This can also be described as a circle circumscribed about a 5-point star.

Star Inscribed In A Circle

Illustration of a 5-point star inscribed in a circle. This can also be described as a circle circumscribed…

A 5-point star made from a non-regular concave decagon in which all sides are equal in length.

Concave Equilateral Decagon

A 5-point star made from a non-regular concave decagon in which all sides are equal in length.

Illustration of a decagonal prism with regular decagons for bases and rectangular faces. The hidden edges are shown.

Decagonal Prism

Illustration of a decagonal prism with regular decagons for bases and rectangular faces. The hidden…

Illustration of a right decagonal prism with regular decagons for bases and rectangular faces.

Decagonal Prism

Illustration of a right decagonal prism with regular decagons for bases and rectangular faces.

Illustration of a right decagonal prism with regular decagons for bases and rectangular faces. The prism is resting on its side, one of the faces.

Decagonal Prism Resting On Its Side

Illustration of a right decagonal prism with regular decagons for bases and rectangular faces. The prism…

Illustration of a swimming pool and water hose that is in the shape of a hollow regular decagonal prism with regular decagons on the ends/bases and square faces.

Swimming Pool Shaped Like A Decagonal Prism

Illustration of a swimming pool and water hose that is in the shape of a hollow regular decagonal prism…

Illustration of a hollow right heptagonal/septagonal prism with regular heptagons/septagons for bases and rectangular faces.

Heptagonal/Septagonal Prism

Illustration of a hollow right heptagonal/septagonal prism with regular heptagons/septagons for bases…

Illustration of a regular right heptagonal/septagonal prism with regular heptagons/septagons for bases and square faces. The hidden edges are shown.

Heptagonal/Septagonal Prism

Illustration of a regular right heptagonal/septagonal prism with regular heptagons/septagons for bases…

Illustration of a right heptagonal/septagonal prism with regular heptagons/septagons for bases and rectangular faces. The hidden edges are shown.

Heptagonal/Septagonal Prism

Illustration of a right heptagonal/septagonal prism with regular heptagons/septagons for bases and rectangular…

Illustration of a right heptagonal/septagonal prism with regular heptagons/septagons for bases and rectangular faces.

Heptagonal/Septagonal Prism

Illustration of a right heptagonal/septagonal prism with regular heptagons/septagons for bases and rectangular…

Illustration of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped decagons and the faces are rectangular.

Star-Shaped Decagonal Prism

Illustration of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped…

Illustration of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped decagons and the faces are squares.

Star-Shaped Decagonal Prism

Illustration of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped…

Side view of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped decagons and the faces are squares.

Star-Shaped Decagonal Prism

Side view of a non-regular decagonal prism in the shape of a star. Then ends/bases are made of star-shaped…

Illustration of 2 similar right decagonal prisms. Both have regular decagons for bases and rectangular faces. The height of the prism and length of the side of the decagon on the smaller decagonal prism are one half that of the larger.

Similar Decagonal Prisms

Illustration of 2 similar right decagonal prisms. Both have regular decagons for bases and rectangular…