In geometry, **2d shapes** and 3d shapes are explained widely to make you understand the different types of objects you come across in real life. These shapes each have their own patterns and properties. The shapes can vary depending on many factors such as angles, sides, lengths, heights, widths, volume, and so forth. These 2D and 3D shapes have been taught to us since our primary classes. This article will cover the various types of two-dimensional shapes.

**Table of Contents:**

- Definition
- Names
- Circle
- Triangle
- Square
- Rectangle
- Pentagon
- Octagon
- Properties
- 2d and 3d Shapes

## 2D Shapes Definition

In maths, 2d shapes can be defined as the plane figures that can be drawn on a flat (or plane) surface or a piece of paper. Each 2d shape has different parameters, such as the area and perimeter. Some 2d shapes have sides and corners while others have curved borders.

## 2D Shapes Names

- Circle
- Triangle
- Square
- Rectangle
- Pentagon
- Octagon

The basic types of 2d shapes are a circle, triangle, square, rectangle, pentagon, quadrilateral, hexagon, octagon, etc. Polygons are any shape that has sides, except the circle. A regular polygon is a polygon that has all angles and sides equal. An ellipse can also be considered a non-polygonal shape, even though it includes the circle. Both the ellipse and circle have a curved form, while the polygons have sides and a closed structure. Let us now discuss a few shapes one-by-one.

### Circle

A circle is a closed 2d figure in which the set of all the points in the plane is equidistant from a given point called “center”. A radius is the distance from the center of the circle to its outer line. Real life examples of the circle include wheels, pizzas, orbits, and so on.

### Triangle

A triangle is a three-sided polygon (2d Shape) which has three edges and three vertices. The sum of all the three angles of a triangle is equal to 180°. The best example of a triangular shape is pyramids. Here are the properties of triangles.

### Square

A square is a four-sided polygon (2d Shape), whose four sides are equal in length and all the angles are equal to 90°. It is a regular quadrilateral of two dimensions. The diagonals of the square also bisect each other at 90°. Square shapes can be used to describe a wall or table with all sides equal.

### Rectangle

A rectangle is a 2d shape which has four sides, where the opposite sides are equal and parallel to each other. All the angles of a rectangle are equal to 90°. You can see the rectangle in bricks, TV, and cardboard. They have length and breadth.

### Pentagon

A pentagon is a five-sided polygon (2d Shape), and it can be regular or irregular. In the case of a regular pentagon, each interior angle is equal to 108°, and each exterior angle measures 72°. It is divided into five diagonals. The pentagon shape is best illustrated by the Pentagon building, which houses the US Department of Defense headquarters.

### Octagon

An octagon is an eight-sided polygon which can be either regular or irregular. It is a 2d form with eight angles. The sum of all the interior angles of an octagon is 1080°. You can see the octagon-shaped stop sign board on the roadside.

### 2D Shapes Properties

Go through the below to learn all the properties of 2D shapes.

## Area and Perimeter of 2D Shapes

The area is the region covered by a 2d shape on a plane. The areas for different shapes are given below:

### 2d Shapes and 3d Shapes

We know that 2d shapes are flat figures and 3d shapes are solid figures. Here are some comparisons between these two types.

## Solved Examples

**Q.1: What is the area of a square that has a side length equal to 4 inches?**

Solution: Given, length of side of square = 4 inches

Area of square = side2 = (4) = 16 in2

**Q.2: What is the area of a circle whose radius is 7 cm? (π=22/7)**

Solution: Given, radius of circle = 7 cm

Area of circle = πr2 = (22/7) x 72 = 22 x 7 = 154 sq.cm.

**Q.3: Determine the perimeter of the rectangle with a length and a breadth of 10 cm and 5cm, respectively. Also, determine its area.**

Solution: Given,

Length of rectangle = 10 cm

Breadth of rectangle = 5 cm

Area of rectangle = Length x Breadth = 10 x 5 = 50 cm2

Perimeter of rectangle = 2(Length + Breadth) = 2(10+5) = 2 x 15 = 30 cms

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