Polyhedra

Edge

A line segment that is formed by the intersection of two faces.

Polyhedron

A solid that is bounded by polygons.

Types of solids

Prism, cone, pyramid, cylinder, and sphere.

Platonic Solids

Regular Polyhedra, regular tetrahedron, a cube, a regular octahedron, a regular dodecahedron, and a regular icosahedron

Regular dodecahedron

Regular Polyhedron with 12 faces, each of which is a pentagon

Regular icosahedron

Regular Polyhedron with 20 faces, each of which is triangle

Cube

Regular Polyhedron with 6 faces, each of which is a square

Regular Tetrahedron

Regular polyhedron with 4 faces, each of which is a triangle

Regular Octahedron

Regular polyhedron with 8 faces, each of which is a triangle.

Cross section

The intersection of a plane and a solid

Euler's Theorem

The sum of the number of Faces and Vertices equals 2 more than the number of Edges.

vertex

a point where three or more edges of a polyhedron meet.

regular

a polyhedron whose faces are all congruent regular polygons.

face

plane that encloses a polyhedron