Pentagon Pentagon In geometry, a pentagon (from the Greek πέντε "pente" and γωνία "gonia", meaning "five" and "angle") 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. A "regular pentagon" has Schläfli symbol {5} and interior angles are 108°. A "regular pentagon" has five lines of reflectional symmetry, and rotational symmetry of order 5 (through 72°, 144°, 216° and 288°). The diagonals of a convex regular pentagon are in the golden ratio to its
The Pentagon million. The Hell's Bottom neighborhood, a slum with numerous pawnshops, factories, approximately 150 homes, and other buildings around Columbia Pike, was also cleared to make way for the Pentagon. Later of land were transferred to Arlington National Cemetery and to Fort Myer, leaving for the Pentagon. Contracts totaling $31,100,000 were finalized with McShain and the other contractors on September 11, and ground was broken for the Pentagon the same day. Among the design requirements, Somervell required the structural design to accommodate floor loads of up to 150 pounds per square foot, which was done in case the building became a