Rationalize the expression. write it in simplest form.

9x/√-2x-11

This appears to be just an expression we are simplifying, not an equation we are solving.  I THINK you are saying that the expression looks like this:

If you rationalize the denominator, you would get this expression:

which, after simplifying, looks like this:

and that's as simple as I can see that one getting.  You can't factor anything out of the denominator to cancel with the numerator, so I think you're as simple as you can get there!