A 12-sided shape is called a dodecagon. A dodecagon is a type of polygon, which is a two-dimensional shape comprised of straight lines. These lines connect to each other to form a closed shape.
Know MoreThe name dodecagon is derived from the Greek words meaning "twelve" (dodeca) and "angles" (gon). Polygons are considered regular polygons if all of their sides and angles are equal. A regular dodecagon has interior angles of 150 degrees. It is also considered a convex dodecagon because none of its interior angles are greater than 180 degrees. Irregular dodecagons have unequal angles and sides. If one of the interior angles is greater than 180 degrees, then it is also a concave dodecagon.
Learn more in GeometryA five-sided polygon is called a pentagon. A pentagon also has five vertices and five interior angles, which add up to a total of 540 degrees.
Full Answer >An 11-sided polygon is called a hendecagon. It is also known as the undecagon or unidecagon. However, the term "hendecagon" takes precedence over these variants because of its consistency in using a Greek prefix and suffix, instead of combining a Roman prefix with a Greek suffix.
Full Answer >A seven-sided shape is called a heptagon. A heptagon is one type of polygon, which can have any number of sides.
Full Answer >A shape with 24 sides is called an icosikaitetragon. Greek prefixes are used for naming shapes by the number of sides. Numbers above 20 have additional special rules that must be followed to construct their names.
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