1. The problem statement, all variables and given/known data 17. xy = 2 3. The attempt at a solution Do you see that step where they do the following: √2/2 - √2/2 = my answer is 0 and they multiply that to √2/2 + √2/2 = my answer is √2 So to me the answer is 0 * √2 = 0, but the book shows that that calculation = 2, then they set x over 2 and y over 2, don't understand why. I don't understand what the book is doing. I understand everything else except that one part.