If y = ( x^2 - y^2)/(x-y) where x not equal to y, then what

Question

If y = ( x^2 - y^2)/(x-y) where x not equal to y, then what is the value of y ?

(1) x + y = 3 
(2) x - y = 2

eyunni · Answer

I chose A but OA is different.

walker · Answer

D

y = ( x^2 - y^2)/(x-y)=(x+y)(x-y)/(x-y)=x+y ==> x=0; for any y.

1. x + y = 3 ==> y=3 suff
2. x - y = 2 ==> y=-2 suff

FN · Answer

I believe the OA is wrong then..

(x-y)(x+y)/(x-y)=y

y=x+y

x+y=3

y=3

sufficient

eyunni · Answer

Can someone look at this problem? This is from GMATClub Challenges
 https://gmatclub.com/tests/m/02/#q25 

Also, is it possible for the variable y to have two different values for 2 cases?

ashkrs · Answer

yes it is possible that you may end up with different values for 2 cases.

In this case it should be D.

1) y = x + y = 3

2) y = x + y => x - y + y = 0 => y = -2

Whatever · Answer

Late, but D.
Agree with walker (same approach)

If y = ( x^2 - y^2)/(x-y) where x not equal to y, then what

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