Here's how to subtract 3/9 from 2/6:
We can't subtract two fractions with different denominators. So you need to get a common denominator. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.
So we multiply 2 by 9, and get 18.
Then we multiply 3 by 6, and get 18.
Next we give both terms new denominators -- 6 × 9 = 54.
So now our fractions look like this:
Since our denominators match, we can subtract the numerators.
18 − 18 = 0
So the answer is:
|Zero divided by anything is just zero. So that's the final answer:|