Illustration of a narrow right circular cylinder (with the height much smaller than the diameter) resting…

Illustration of a plane passing through a cylinder. Every section of a cylinder made by a plane passing…

Illustration of a plane passing through a cylinder. Every section of a cylinder made by a plane passing…

Illustration of a right circular cylinder with the height larger than the diameter.

Illustration of 2 narrow right circular cylinders with equal heights (thickness) and different diameters.…

Illustration of 2 right circular cylinders in which one cylinder is twice the height of the other.

Illustration of 2 right circular cylinders in which one cylinder is twice the height and twice the diameter…

Illustration of 3 right congruent tangent circular cylinders. The height of all the cylinders is greater…

Illustration of 3 right congruent tangent circular cylinders.

Illustration of 3 right congruent tangent circular cylinders. The height of all the cylinders is greater…

Illustration of 4 congruent tangent right circular cylinders. The height of all the cylinders is greater…

Illustration of a decagonal pyramid that has been cut by a plane parallel to the base. The top section…

Illustration of a hollow decagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a decagonal pyramid that has been cut by a plane parallel to the base. The top section…

Illustration of a hollow septagonal/heptagonal pyramid that has been cut by a plane parallel to the…

Pattern that can be cut out and folded to construct a regular dodecahedron. Fold on the dotted lines,…

The frustum of a pyramid is the portion of a pyramid included between the base and a section parallel…

The frustum of a triangular pyramid is equivalent to the sum of three pyramids whose common altitude…

Illustration of a right hexagonal pyramid that has been cut by a plane parallel to the base. The lower…

Illustration of a right hexagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right hexagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right hexagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a skewed hexagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration showing the combination of a hexahedron and an dodecahedron.

Pattern that can be cut out and folded to construct a regular hexahedron. Fold on the dotted lines,…

Pattern that can be cut out and folded to construct a regular icosahedron. Fold on the dotted lines,…

Illustration of a hollow nonagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right octagonal pyramid, with hidden edges shown, that has been cut by a plane parallel…

Illustration of a right octagonal pyramid that has been cut by a plane parallel to the base. The lower…

Illustration of a hollow octagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration showing the combination of a octahedron and an dodecahedron.

Pattern that can be cut out and folded to construct a regular octahedron. Fold on the dotted lines,…

Illustration of a parallelopiped with a plane passing through two diagonally opposite edges. The plane…

Illustration of a parallelopiped with a plane passing through two diagonally opposite edges. The plane…

Illustration of a parallelopiped (a prism with a parallelogram as its base) used to demonstrate that…

Illustration of a right pentagonal pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a hollow pentagonal pyramid that has been cut by a plane parallel to the base. The top…