A pentagon is a five-sided polygon. Several special types of pentagons are illustrated above. In particular, a pentagon with vertices equally spaced around a circle and with all sides the same length is a regular polygon known as a regular pentagon.
Pentagon
See also
Decagon, Hexagon, Octagon, Polygon, Regular Pentagon Explore this topic in the MathWorld classroomExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Pentagon." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Pentagon.html