A decagon is a polygon that consists of ten sides and ten angles. The word “decagon” is derived from the Latin words “deca,” meaning ten, and “gonia,” meaning angle. It is classified as a regular polygon because all of its sides have equal lengths and all of its angles have equal measures.
Properties of a Decagon:
- Sides: A decagon has ten sides, which means it has ten line segments connecting its ten vertices (corner points).
- Angles: Each interior angle of a decagon measures 144 degrees, and each exterior angle measures 36 degrees. The sum of all the interior angles of a decagon is 1440 degrees.
- Symmetry: A decagon exhibits rotational symmetry of order 10, which means it can be rotated by multiples of 36 degrees to coincide with its original position.
- Diagonals: A decagon has 35 diagonals, which are line segments connecting any two non-adjacent vertices.
- Area: To calculate the area of a regular decagon, you can divide it into ten congruent isosceles triangles.
In practical terms, a decagon can be observed in various contexts. For example, a stop sign typically has the shape of a regular octagon with a smaller octagonal region in the middle, creating a decagon-like appearance.