2x+12 would be the answer
Rationalizing the denominator, simply means "getting rid of that pesky root at the bottom", and we do so by simply multiplying it by something to take it out, of course, we multiply the bottom, we have to also multiply the top,

I’m really sorry. I really try to figure this out but I’m Real bummed out that I can’t even get this. What even is this question? Like tell me the answer if you can even find out ._.
Look at each term. How does the next one change? what is added?
The answer is 6, because there is an increase of 6 for each term