Question

Simplify square root of 18.

Answer 1

What numbers multiply together to give 18?

Answer 2

9 and 2

Answer 3

6 and 3

Answer 4

18 and 1

Answer 5

good. Is either of these a perfect square?

Answer 6

what is a perfect square?

Answer 7

a number that is the square of another number. So 5^2=25 , making 25 a perfect square.

Answer 8

neither of those is a perfect square.

Answer 9

wait

Answer 10

you gave me six numbers, 2,9,6,3, 18 and 1. are any of those perfect squares?

Answer 11

i dont think so?

Answer 12

1 x 1 =1
2 x 2 =4
3 x 3 = ?

Answer 13

9

Answer 14

So 9 is a perfect square since its 3 squared.

Answer 15

Ohh that makes sense

Answer 16

so 3 to the square root of 2

Answer 17

so now if \[\sqrt{18} = \sqrt{9 \times 2} \] what can we say about \[\sqrt{18}?\]

Answer 18

square root of 18 is 9 to the square root of 2?

Answer 19

not quite. Think about the \[\sqrt{36} =\sqrt{4 \times 9} = \sqrt{4} \times \sqrt{9} = 2 x 3 =6\]

Answer 20

I dont get it

Answer 21

If I have two numbers, a and b, its always true that\[\sqrt{a time b} = \sqrt{a} \times \sqrt{b}\], so if 18 = 9 x 2 ....

Answer 22

\[2\sqrt{?9}\]

Answer 23

make that \[\sqrt{a \times b} = \sqrt{a} \times \sqrt{b}\]

Answer 24

In oour case, a x b =18, so we can take a=9 and b=2...

Answer 25

ok

Answer 26

is that the answer?

Answer 27

\[2\sqrt{9}\] isn't quite correct, but you're getting close

Answer 28

\[9\sqrt{2}\]

Answer 29

closer remember that \[\sqrt{a \times b} = \sqrt{a} \times \sqrt{b}\]
so you need to take the square root of both factors

Answer 30

ohh so its \[3\]

Answer 31

\[3\sqrt{2}\]

Answer 32

perfect!

Answer 33

sweet. ty