The y^0.5 was the same as sqrt y, and since x^2=y therefore x= sqrt y
so whatever you got for x, I believe you had to square your answer.
**only picked this up from doing solomon papers
I still felt it was abit easier than last year tho, i'm more worried about C2, i feel like it'll really screw us over.
However I suggest going through all the solomon papers, there aren't really much tho so its doable and after do some standard papers and you should be alright mate