In this chapter we will learn about irregular polygon with properties and examples.

Let us first review the basics of polygons.

## What is Polygon ?

Polygon is a **two dimensional closed shape made by straight lines**.

The polygons has been named on the basis of number of sides.

**For example;**

Polygon with 5 sides is known as Pentagon.

Polygon with 8 sides is known as Octagon and so on.

## What is Irregular Polygon?

The** polygon in which all angles and sides are not equal** are called **irregular polygon**.

The irregular polygon shows following features;

(a) All side length is not equal.

(b) Interior angles are also different.

(c) Irregular Polygon can be of two types; convex and concave.

⟹ **Convex Irregular Polygon**

It is a irregular polygon in which all the interior angles are less than 180 degree

⟹ **Concave irregular Polygon**

It’s a irregular polygon in which one of the interior angle is greater than 180 degree.

All the concave polygons are irregular polygons.