# Polygons - Classification, Angles

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word comes plane term

Polygons are closed **plane** figures bounded by three or more line segments. In the world of **geometry**, polygons abound. The **term** refers to a multisided geometric form in the plane. The number of angles in a polygon always equals the number of sides.

Polygons are named to indicate the number of their sides or number of noncollinear points present in the polygon.

A **square** is a special type of polygon, as are triangles, parallelograms, and octagons. The prefix of the term, *poly* comes from the Greek word for many, and the root word *Gon* comes from the Greek word for **angle**.

## Additional Topics

A regular polygon is one whose whose sides and interior angles are congruent. Regular polygons can be inscribed by a circle such that the circle is tangent to the sides at the centers, and circumscribed by a circle such that the sides form chords of the circle. Regular polygons are named to indicate the number of their sides or number of vertices present in the figure. Thus, a hexagon has six side…

In a polygon, the line running between non-adjacent points is known as a diagonal. The diagonals drawn from a single vertex to the remaining vertices in an n-sided polygon will divide the figure into n-2 triangles. The sum of the interior angles of a convex polygon is then just (n-2)* 180. If the side of a polygon is extended past the intersecting adjacent side, it defines the exterior angle of th…

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## User Comments

about 9 years ago

i reallty need help learning about polygons.I have had teachers take their timw worj=king with after school,intill i had seen this page and it really help me out alot thanks page.