Is x=y? 1) (x-y)= (x^2-y^2) 2) X and Y are each greater than

Question

Is x=y?

1) (x-y)= (x^2-y^2)

2) X and Y are each greater than 1

cmohannayak · Answer

a. x-y = x^2 - Y^2 
 = ( x + y) (x -y)
 
 For this to be true either x + y = 1,0 or x - y = 0

b. Tells us that both numbers are greater than 1.

c. Since both numbers are greater than 1 , x + y is not equal to 0. 
 which leaves x -y = 0 
 
 therefore x = y

Option C

chicagocubsrule · Answer

Statement 1:
By plugging in numbers you can disprove this. Example:
x = 1
y = 0

1 - 0 = 1^2 - 0^2

Statement 2:
X & Y are greater than 2....real nice but doesn't help us out

Statements 1 & 2:
Prove that X & Y are indeed equal

kman · Answer

1) INSUFF
 can be written as 
  x^2-y^2 - (x-y) = 0 
  (x+y)(x-y) - (x-y) = 0 
  (x-y)   = 0 
 ==>  x=y  or  x+y=1

2) INSUFF. Only tells us both are > 1

1 and 2 combined, we can say that x+y=1 not possible because both are >1. Then x=y

pmenon · Answer

you guys are correct. so here is my question regarding statement 1:

x^2-y^2 = (x-y)(x+y) = x-y

why can i not just divide both sides by x-y to get x+y=1 ? This is what I did, and I answered A because from x+y=1, its clear that x does not equal y.

GMATpp · Answer

you can divide both side but you have to make sure that number is not zero 
but this problem x - y has a possible to be zero

Is x=y? 1) (x-y)= (x^2-y^2) 2) X and Y are each greater than

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