What are Polygons?
- A Polygon is a closed figure made up of lines segments (not curves) in two-dimensions.
- A minimum of three line segments are required for making a closed figure, thus a polygon with a minimum of three sides is known as Triangle.
Depending on the sides and angles, the polygons are classified into different types, namely
- Regular Polygon
- Irregular Polygon
- Convex Polygon
- Concave polygon
If all the sides and interior angles of the polygon are equal, then it is known as a regular polygon.
If all the sides and the interior angles of the polygon are of different measure, then it is known as an irregular polygon.
If all the interior angles of a polygon are strictly less than 180 degrees, then it is known as a convex polygon. The vertex will point outwards from the centre of the shape.
If one or more interior angles of a polygon are more than 180 degrees, then it is known as a concave polygon. A concave polygon can have at least four sides. The vertex points towards inside of the polygon.
Classification of Triangles
In our article on Geometric Shapes, we discussed the polygons with the least number of sides – the Triangle. In this section, we will go through different types of triangles.
- Equilateral triangle – Having all sides equal.
- Isosceles triangle – Having any 2 sides equal.
- Scalene triangle – All 3 unequal sides.
- Acute angled Triangle– Each angle is less than 900
- Right Angled Triangle– Any one angle is 900
- Obtuse Angled Triangle– Any one angle is greater than 900
|An interesting fact about Triangle:
A Quadrilateral is a polygon having the number of sides equal to four.
The table below gives the comparison of Opposite sides, angles, and diagonals of different Quadrilateral.
|Quadrilateral||Opposite||Sides||All sides Equal||Opposite angles equal||Diagonal|
(Only one side)
Polygon: A general comparison
|Polygon||No. of Sides||No. of Diagonal||No. of vertices||Interior Angle|
Three Dimensional Shape (3-D shape)
- These are the shapes that can be projected on a piece of paper but cannot be drawn on a paper. These shapes are known as solids.
|2-D shape (Polygon)||3-D Shape|
- 3-D shapes have Faces as the distinguishing Feature.
To know more about polygons, types of polygons and 3-D shapes, download BYJU’S the Learning App.