You can
put this solution on YOUR website!
Start with the given expression

Convert to radical notation

Multiply both numerator and denominator by

Combine the fractions

Multiply

to get

where y is positive

Divide

by

to get
So

simplifies to
Your answer is correct. The only difference between our answers is the notation. Try to enter the answer

and let me know if it works out (since I'm assuming that this is what they are looking for).
Note: On the page, there should be a guide for the answer format (ie something that tells you what they want). If it is not on the page, try looking elsewhere (maybe in the syllabus?). I'd say the best option is to ask your instructor as s/he will know what to enter.