## anonymous one year ago How do I know if it is rational or not? http://i.imgur.com/OGtUJyY.png

1. ganeshie8

$2\sqrt{3}*\sqrt{12} = 2\sqrt{3*12} = 2\sqrt{36} = 2*6 = 12=\dfrac{12}{1}$

2. ganeshie8

It is a ratio of two integers, so it is rational.

3. anonymous

So if it can be written as a ration, its rational?

4. ganeshie8

Exactly!

5. anonymous

Wat about $2\sqrt{3}-2\sqrt{3}$

6. anonymous

What*

7. anonymous

I think it's irrational because the outcome is 0 and 0 cannot be written as a ratio.

8. ganeshie8

$0 = \dfrac{0}{1}$ every integer is rational