Pentagon
Shape with five sides / From Wikipedia, the free encyclopedia
This article is about the geometric figure. For the headquarters of the United States Department of Defense, see The Pentagon. For other uses, see Pentagon (disambiguation).
In geometry, a pentagon (from Greek πέντε (pente) 'five' and γωνία (gonia) 'angle'[1]) is any five-sided polygon or 5-gon. The sum of the internal angles in a simple pentagon is 540°.
A pentagon may be simple or self-intersecting. A self-intersecting regular pentagon (or star pentagon) is called a pentagram.