I think this question is missing something.
As it stands, we're told that x - y > 0. In other words, x - y is POSITIVE

Then we're told that \(\sqrt{(x-y)}=\sqrt{-1}\)
This means x - y = -1
However, we earlier learned that x - y is POSITIVE

Cheers,
Brent
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x-y>0 ; X>1 ; \(\sqrt{(x-y)}=\sqrt{x}-1\)

Let us square \(\sqrt{(x-y)}=\sqrt{x}-1\)..
\(\sqrt{(x-y)}^2=(\sqrt{x}-1)^2........ x-y=x+1-2√x....y=2√x-1.....A=B\)

C
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