A regular pentagon has Schläfli symbol {5} and interior angles of 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 sides. Given its side length , its height (distance from one side to the opposite vertex), width (distance ...

The Pentagon is the headquarters building of the United States Department of Defense.It was constructed on an accelerated schedule during World War II.As a symbol of the U.S. military, the phrase The Pentagon is often used as a metonym for the Department of Defense and its leadership.. Located in Arlington County, Virginia, across the Potomac River from Washington, …

Les Pentagon Papers (« papiers du Pentagone ») est une expression populaire désignant le document United States-Vietnam Relations, 1945-1967: A Study Prepared by the Department of Defense (« Relations entre les États-Unis et le Viêt Nam, 1945-1967 : une étude préparée par le département de la Défense »). Il s'agit de 47 volumes totalisant 7 000 pages secret-défense …