So, now you've become familiar with powers and square numbers. But there is another associated term which you'll come across a great deal in KS3 Maths - square roots.

No, they're not parts of plants shaped like cubes! Square roots are the opposite of square numbers. Here are a couple of examples: the square of 3 is 9 (3 x 3) so the square root of 9 is 3. The square of 8 is 64 (8 x 8) so the square root of 64 is 8. All numbers have their own square root. But most are not as easy to work out as the above examples. The square root of 4 is 2 and the square root of 9 is 3. But what is the square root of 6? The answer is 2.449489742783178. Sometimes you just have to use a calculator!

It might seem a little confusing at first but this Maths quiz will help you sort out your squares from your square roots! Read each question carefully and take your time choosing your answers. Good luck!

1.

What is the square root of 16?

2 or -2

4 or -4

6 or -6

8 or -8

Both 4 x 4 and -4 x -4 = 16

2.

What is the square root of 81?

3 or -3

6 or -6

9 or -9

12 or -12

9 x 9 = 81 AND -9 x -9 = 81

3.

You are given the two numbers '3 squared' and 'the square root of 100'. How do they relate to each other?

3 squared is the larger number

The square root of 100 is the larger number

They are both the same

There is no way of telling

The square root of 100 could be either 10 or -10 and we have no way of knowing which square root the question requires!

4.

Which of these numbers has a whole number as a square root?

30

32

34

36

6 x 6 = 36

5.

Which of these figures does not have a whole number as a square root?

25

35

49

64

The square root of 35 is 5.916079783099616

6.

The √ sign is referred to as what?

Square

Squared

Square root

Square rooted

It's important you get to know what the square root sign looks like

7.

What is the quickest way to find the square root of 8?

Divide 8 by 2

Multiply 8 x 2

Take 2 from 8

Use a calculator

Some square roots are not whole numbers and can be very difficult to work out. The square root of 8 is approximately 2.828427. We used a calculator to find out!

8.

What is the square root of 100?

2 or -2

10 or -10

25 or -15

50 or -50

Minus numbers multiplied by themselves always give a positive answer. So, strange as it seems, -10 x -10 = 100

9.

You are given the two numbers '9 squared' and '81'. How do they relate to each other?

81 is the larger number

9 squared is the larger number

They are both the same

They are in no way related

9 x 9 = 81

10.

What is the square of 9?

3

6

9

81

Did you spot that we asked for the 'square' and NOT the 'square root'?

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