Hello mandyn318

Welcome to Math Help Forum!This looks easy, but I think it's surprisingly tricky. I have a proof that assumes and . I'll leave it to you to check what happens if you take the negative values of the square roots.

To make it easier to read, then, I'm going to let:andSo:

and , taking the positive square rootsTherefore the original given equation:

can be written as:Now

...(1)

Grandad, from the original given

, multiplying top-and-bottom by

from (1)