Geometry

What are Polygons? Types of polygons

What are  Polygons. Types of polygons

A polygon is a closed plane figure with straight
sides. like triangles and squares.

Polygons are 2-dimensional shapes. They are made
of line segments (straight lines), and the shape is
closed.

The Vertex is endpoint where the two sides meet.

 

These figures are examples of polygons

polygons
 

These figures are examples of non-polygons

non-polygons
 

Simple or Complex

A polygon is simple if it is described by a single, 
non-intersecting boundary; otherwise it is said to be
complex.

Simple and Complex polygons
 

Regular or Irregular

A polygon is called regular if all its sides are of equal
length and all its angles are equal. Otherwise it is
irregular.

Regular and Irregular polygons
 

Concave or Convex

Polygons can be Convex meaning all angles (vertex) are facing out like
most of the Polygons above. Are they could be concave or non-convex
Polygons with one or more angles (vertex) pointing in. Like the one to the
right.

 

Triangles and squares are two examples of Regular Convex Polygons

 

Names of Polygons

Polygons can be   named by how many sides they have, 
starting from the Triangle which has three sides.