Polygon Definition

In Geometry, Polygon is a close shape that is made by joining different line segments. It is a two-dimensional figure that has three or more straight sides. The sides of a polygon are called Edges while the joining points are called Vertices.

Note:

Read about Line Segment, Edges, and Vertices here.

Common Examples of Polygons in Geometry

In this field of Mathematics, we see multiple closed figures but not all of those are polygons. Here are a few examples of a Polygon that students have to deal with commonly.

  • Triangle
  • Rectangle
  • Square
  • Hexagon
  • Quadrilateral

How to check if a figure is Polygon?

To check if a figure is Polygon or not, you should classify the figure based on the following points.

  • The number of sides and angles should be equal to each other.
  • No curved side should be involved in the figure

If a figure is fulfilling these requirements, it will be a Polygon. Otherwise, it is just a close shape not considered to be a part of a collection of Polygons.

Properties of a Polygon

  • It is a closed shape.
  • It lies in a two-dimensional plane.
  • It doesn’t include any curved side or length.
  • A polygon has at least three sides.

Types of Polygon

Depending on the measurement of lengths and angles involved, Polygon is classified into two major types. Here is a brief discussion about those types.

Note:

Read about a Regular Polygon and Square here.

  • Regular Polygon: In this type, the length of sides and measures of angles must be the same. It means all sides have equal lengths and all angles have equal measures. For example, a “Square” is a Regular Polygon

Note:

Read about an Irregular Polygon and Scalene Triangle here.

  • Irregular Polygon: In this type, lengths of all sides and measures of all angles are different. It is a closed figure with different lengths of sides. For example, a “Scalene Triangle” is an Irregular Polygon because it has lengths and angles of different measures.

Operations on a Polygon

Like other figures involved in Geometry, different operations can be applied to a Polygon. The most common operations are Area Measurement and Perimeter Measurement. Let us explain them here briefly for understanding.

Area Measurement

The area is the total region covered by any figure (a Polygon in this case). The formula to measure the Area of a Polygon depends on the type of a Polygon and its configuration. For example, the Area of a Triangle is different from the Area of a Rectangle even though both are Polygons.

Note:

Read about Area here in detail.

Perimeter Measurement

Perimeter is the sum of the distance covered by different sides of a Polygon. To find Perimeter, we have to evaluate the type of the given Polygon.

FAQ's

What is a Polygon?

It is a two-dimensional closed shape made by joining straight lines.

Can a Polygon has 6 sides?

Yes, a Polygon has 6 sides. To be a Polygon, a figure has at least three sides.

What are the two main types of polygons?

The two major types of Polygons are defined on the basis of length and angle measurements. Here are the names of those types.

  • Regular Polygon
  • Irregular Polygon

Is the circle a Polygon?

No, a circle is not a Polygon because it is made by joining dots and doesn’t have straight lines.

Can a polygon have a different number of angles and sides?

No, a polygon must have an equal number of sides and angles.

How to check if a polygon is regular or not?

If a polygon has all sides and angles of equal measure, it will be a Regular Polygon. Otherwise, it will be an Irregular Polygon.

How to identify a Polygon?

A figure is a Polygon only if it fulfills the following requirements,

  • It must be a closed shape.
  • It must have an equal number of sides and angles.
  • It must be a two-dimensional shape.

Are all triangles ate Polygons?

Yes, all triangles are Polygons.