Solve and Reduce are happiest with polynomial equations. The nested square roots are hard for them to digest.
It would be helpful for potential helpers if the code could be posted in machine-readable form.
- select (click once) the cell bracket for the cell,
- go to Edit menu, Copy As, and pick Cell Expression,
- in a reply to this thread, click the spikey
in the top of the reply area,
- paste the Cell Expression for your input cell into the reply area.
The result can be copied and pasted into a Mathematica notebook for experimenting.
Simpler methods of copying and pasting are likely to loose typesetting.