Table of Contents

**Class 7 Maths Perimeter and Area – Perimeter of a Square and a Triangle **

**Table of Contents**

- Perimeter of a Square
- Perimeter of a Triangle
- Summary
- What’s Next?

In our previous segment of Class 6 Maths, we learnt about The **Perimeter of a rectangle. **In this segment, under the use of variables in common rules, we will learn about the Perimeter of a square and a triangle.

## What is the Perimeter of a square?

The total sum of the lengths of the sides of a square gives us its perimeter.

Consider a square with a side of length ‘S’. As all sides of the square are equal, each side of the square will be S.

Thus, the perimeter of the square = S + S + S + S

= 4S

So, the Perimeter of the square is 4S, that is, 4 times the length of a side of the square. For example,

If the side of a square is 7 cm, then its perimeter is given by,

Perimeter of the square = 4S

= 4 x 7

= 28 cm.

So, the perimeter of the square is 28 cm.

## What is the Perimeter of a triangle?

The Perimeter of a triangle is the total length around the triangle.

Consider a triangle with sides of lengths ‘a’, ‘b’, and ‘c’.

Thus, the perimeter of the triangle = a + b + c.

For example,

If the sides of a triangle are 13 cm, 10 cm, and 5 cm, then its perimeter is given by, Perimeter of the triangle = a + b + c

= 13 + 10 + 5

= 28 cm.

So, the perimeter of the triangle is 28 cm.

## Summary

Perimeter of a Square |
4 x side, that is, 4S |

Perimeter of a Triangle |
Sum of all sides |

**What’s next?**

In our next segment of Class 6 Maths, we shall deal with the **Commutative property of whole numbers.**