How many sides does a pentagon have? A pentagon has number ___sides.
The correct answer and explanation is:
A pentagon has 5 sides.
The name “pentagon” comes from the Greek words “pente,” meaning five, and “gonia,” meaning angle. So, a pentagon is a polygon with five straight sides and five angles. In geometry, polygons are classified based on the number of their sides. For example, a triangle has three sides, a quadrilateral has four sides, and a hexagon has six sides. Each side of a pentagon is typically of equal length if it is a regular pentagon, and the interior angles of a regular pentagon each measure 108 degrees.
In addition to the regular pentagon, where all sides and angles are equal, there are also irregular pentagons. These do not have equal sides or angles but still have five sides. The sum of the interior angles in any pentagon is always 540 degrees, regardless of whether it is regular or irregular. This can be calculated using the formula for the sum of interior angles of a polygon:
Sum of interior angles = (n – 2) × 180
Where n is the number of sides. For a pentagon (n = 5):
(5 – 2) × 180 = 3 × 180 = 540 degrees.
The pentagon is commonly seen in various fields and designs. For example, in architecture, a pentagon can be used as a structural shape. It is also the shape of the famous Pentagon building in the United States, which serves as the headquarters of the U.S. Department of Defense.
Overall, understanding the properties of polygons like the pentagon helps in a wide range of subjects, from architecture and engineering to art and design.