One term used for a 3D pentagon is a shape called a pentagonal prism. According to, this is the polygon that results when you take a pentagon, transcribe a copy of it, and connect the two pentagons using fi... More »

A pentagon is a two-dimensional geometric figure that has five sides. A regular pentagon is one where all five sides are the exact same length and the internal angles are all 108 degrees. More »

There are examples of pentagons in real life in man-made structures like the Pentagon in the United States, and also in nature in flowers like morning glories and okra. Other items, like home plates in baseball, are ofte... More »

A pentagon has five diagonals on the inside of the shape. The diagonals of any polygon can be calculated using the formula n*(n-3)/2, where "n" is the number of sides. In the case of a pentagon, which "n" will be 5, the ... More »

The term "geometric shape" refers to any shape that remains virtually unchanged if it is moved around, flipped or reflected off of a surface. When manipulated, a geometric shape does not create a new shape; it remains in... More »

Usually when a person refers to a "three-dimensional pentagon," he is referring to a regular dodecahedron. A dodecahedron is a solid made of 12 flat faces, and a regular dodecahedron is made of 12 regular pentagons. More »

A rectangular prism is a three-dimensional object that has six faces that are all rectangles. On a rectangular prism, opposite faces are both equal and parallel. Rectangular prisms also have the same cross section along ... More » Math Geometry Shapes