Square roots are numbers that, when multiplied by itself, will give the original nonnegative numbers.

Example: 6 times 6 = 36 and −6 times −6 = 36.

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Video Transcript.

Recall this:

x^{2} = x times x, or x・x

This is the “Square of a Number” or the number squared.

The number x^{2} is called the square of the number x.

So, for example:

9^{2 }= 9・9 which equals 81. So, the number of 81 is the square of our number 9.

– 4^{2} = – 4・- 4 which equals 16. So, the number of 16 is the square of our number −4.

Below the video, we’ve put a “List of Squares” of all whole numbers from 0 (zero) through 25. Please check that out.

**Square Roots**

By the time you’ve mastered the concept of squaring whole numbers, you are all set for the inverse process of squaring: determining square roots of whole numbers.

Above, we’ve seen that 9^{2 }equals 81.

We named that number 81 a square of our number 9.

We name that number 9, conversely, a square root of our number 81.

We’ve also seen that – 4^{2 }equals 16. We named the number of 16 the square of our number −4.

We name −4, conversely, a square root of our number 16.

Square Roots

So when a^{2} = b, we call the number “a” a square root of the number “b”.

For example, let’s find the square roots of 49.

Well, to find a square root of the number 49, we need to think of a number in a way that a^{2} = 49. Now, two (2) numbers come to mind:

7^{2 }equals 49. So the number 7 is a square root of our number 49.

-7^{2 }equals 49. So the number -7 is also a square root of our number 49.

So you notice that our number 49 has two (20) square roots, a positive one and a negative one.

## List of Squares

It may be a good idea is you would memorize this list. This may well help you manage your time at your GED Math Test.