Shapes

Have you noticed the shape of a pizza? It is round in shape.

Pizza is round in shape

If we cut out a slice from the pizza, the slice gets a triangular shape.

A slice of pizza in triangular in shape

In this lesson, you will learn all about shapes, types of shapes, and geometric shapes. Check out the interactive simulations to know more about the lesson and try your hand at solving a few interesting practice questions at the end of the page. So, what are you waiting for?

Let's begin!

Lesson Plan

What are Shapes?

A shape can be defined as the boundary or outline of an object. It is the surface we see and does not depend on the size or the color of the object.

Everything around us has a different shape, such as the square, rectangle, or three-dimensional sphere. Have you seen the model of the Earth called the globe? What is the shape of this globe?

A globe model showing the Earth is sphere in shape

It looks like a sphere.

Now, look at this pencil box.

A pencil box in cuboid shape

It looks like a cuboid.

Types of Shapes

Shapes define the boundary of an object and can be differentiated in many ways based on their properties.

Shapes can be of various types:

Closed Shapes

Closed shapes can be traced without any break. They start and end in the same place.

Let's look at these examples:

Closed shapes

Open Shapes

Open shapes are not continuous and are made up of line segments or curves which do not meet.

open shapes

Two-dimensional \((2\text{D})\) or three-dimensional \((3\text{D})\) shapes

A shape can be two-dimensional (\(2\text{D}\)) or three-dimensional (\(3\text{D}\)).

A square is a \(2\text{D}\) shape, whereas, a cube is a \(3\text{D}\) shape.

\(3\text{D}\) shapes have a length, a width, and a height. You can learn more about it here.

\(2\text{D}\) shapes, as the name suggests, have only two of these measurements.

2D Vs 3D shapes in maths

The common \(2\text{D}\) and \(3\text{D}\) shapes are listed here in Table - 1 and Table - 2.


List of Geometric Shapes

We know that shapes are made of straight lines or curved lines and they can be open or closed.

Lines are defined as a collection of points. In other words, many points put together to form a line.

They may form a straight line or a curved line.

Geometric shapes are closed shapes which are created by joining lines together.

Look at this shape below; this is made of four straight lines.

4 sided shape made of straight lines

Closed shapes made of four straight lines are called quadrilateral shapes.

Can you think of another quadrilateral shape?

Next, look at this shape:

elliptical shape

It has no straight line, corner, or side to it. It is a closed shape made of curved lines.

This shape is called an ellipse.


What are Two-Dimensional Shapes?

Observe this sheet of paper.

A sheet of paper is 2 dimensional in shape

It consists of a length and a width.

A two-dimensional shape does not have any depth.

The common \(2\text{D}\) shapes we see are listed below:

Table - 1

\(2\text{D}\) Shapes Name Number of sides Image
Triangle \(3\) A triangle is a 2D shape
Square \(4\) A square is a 2D shape
Rhombus \(4\) A rhombus is a 2D shape
Kite \(4\) A kite is a 2D shape
Rectangle \(4\)

Rectangle is a 2D shape

Trapezium \(4\) A trapezium  is a 2D shape
Pentagon \(5\) A pentagon is a 2D shape
Hexagon \(6\) A hexagon is a 2D shape
Heptagon \(7\) A septagon 7 sided polygon
Octagon \(8\) An octagon is a 2D shape
Decagon \(10\) A decagon is a 10 sided polygon
Dodecagon \(12\) A dodecagon twelve sided polygon
Hexadecagon \(16\) A hexadecagon is a 16 sided polygon
Circle \(0\) A circle is a 2D shape

Can you draw a few more \(2\text{D}\) shapes?


What are Three-Dimensional Shapes?

Have you seen a dice?

A dice , 3D shape

This is a three-dimensional shape. It consists of a length, a breadth, and a height.

Three-dimensional shapes have some thickness or depth.

This shape is called a cube. There are several other \(3\text{D}\) shapes.

A few are listed here in the table:

Table - 2

\(3\text{D}\) Shapes Name Images
Cuboid  A cuboid is a 3D shape
Cone Shape of a cone is a 3D shape 
Pyramid Shape of a pyramid is a 3D shape 
Cylinder A cylinder is a 3D shape



 

Look around you and identify more \(3\text{D}\) shapes.

 
important notes to remember
Important Notes
  1. Quadrilateral shapes are four-sided closed figures made with straight lines.
  2. Polygons are closed geometric shapes made of straight lines. They are named after the number of sides they have.Math Notes

Solved Examples

Example 1

 

 

Does the given figure have a two-dimensional or a three-dimensional shape? How many sides does it have?

Shape of a football is spherical

Solution

The football looks like a sphere and has \(0\) sides.

The figure has a three-dimensional shape
Example 2

 

 

John ordered an ice-cream at an ice-cream parlor.

What \(3\text{D}\) shape does the ice-cream resemble?

Cone shaped ice cream

Solution

The ice-cream resembles a cone.

It looks like a cone
Example 3

 

 

How many sides are there in the given shape? Is it a closed or an open shape?

Number of sides in a star shape

Solution

Count the number of straight lines in the star. There are \(10\) straight lines.

We can trace the outline of this star without any break. Hence, it is a closed shape.

It is a closed shape with \(10\) sides
Example 4

 

 

Alex went to a gift shop to buy a gift for his friend.

He bought building blocks for him.

He wants to pack his gift in a box.

Can you help him find the right box to place the gift?                  

Gift box

Solution

The given gift boxes are in the shape of a cylinder, sphere and cube.

The building blocks are in the form of a cube.

Therefore, the box shaped like a cube is the right shape to pack the building blocks.

Building blocks fit in the cube shaped box

Thus, Cube is the right shape.

Interactive Questions

Here are a few activities for you. Select/Type your answer and click the "Check answer" button to see the results.

 
 
 
 
 
 
 
Challenge your math skills
Challenging Questions
  1.  Is the given shape a Quadrilateral? 
    A shape that is not a quadrilateral
  2.  What is the name of the closed shape which has 100 sides?

Let's Summarize

We hope you enjoyed learning about Shapes with the simulations and practice questions. Now you will be able to easily solve problems on shapes names, all shapes, types of shapes, and geometric shapes.

About Cuemath

At Cuemath, our team of math experts are dedicated to make learning fun for our favorite readers, the students! 

Through an interactive and engaging learning-teaching-learning approach, the teachers explore all angles of a topic. 

Be it problems, online classes, videos, or any other form of relation, it’s the logical thinking and smart learning approach that we at Cuemath believe in.


Frequently Asked Questions (FAQs)

1. What do you call a 9 sided shape?

A 9-sided shape is called a Nonagon.

2. How do you identify shapes?

A great way to identify shapes is by knowing the number of sides and points in it.

For Example: A triangle has 3 sides and 3 points. So, we can easily identify it as a triangle.

3. What do you call a 10 sided shape?

A 10-sided shape is called a Decagon.

  
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