Square root is a value that when multiplied by itself, gives the original number.

(√ )This is the radical symbol used to represent the square root of numbers.

**Formula to calculate square root.**

Usually, most people use calculators to calculate the square roots of numbers, which is very easy and more convenient when time is a factor to be considered.

There are many methods to calculate square root by hand, but we will use the one that uses a number’s factors to find the number’s square root.

**Example:**

Find the square root of 400.

We first need to know the two perfect squares whose product is 400 and they are 25 and 16.

Since 25 and 6 are perfect square and most people know that their square roots are 5 and 4 respectively, then to know the square root of 400, we will multiply 5 by 4.

= 5 x 4

= 20

Therefore, 20 is the square root of 400.