Geometry: Polygons

A Polygon is a closed plane figure made up of several straight line segments that are joined together. The sides do not cross each other and exactly two sides meet at every vertex.


Triangles and quadrilaterals (including trapezoids and all kinds of parallelograms) are examples of polygons (see Figure above, top). Other examples are shown in this Figure bottom also (regular pentagon, regular and irregular hexagons, and non-convex quadrilateral).

Lessons under this topic consider properties of polygons.

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