IS (x+y)(x-y)>0
From 1 x>|Y|
hence X is positive ..so (x+y) and (x-y) will be both positive...(x+y)(x-y)>0 ..sufficient
From 2
|x|>y
So (x+y)(x-y)>0 ..sufficient
Ans option D
41) MOD DS
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Source: Beat The GMAT — Data Sufficiency |
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liferocks
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we can re write the question as
IS (x+y)(x-y)>0
From 1 x>|Y|
hence X is positive ..so (x+y) and (x-y) will be both positive...(x+y)(x-y)>0 ..sufficient
From 2
|x|>y
So (x+y)(x-y)>0 ..sufficient
Ans option D
IS (x+y)(x-y)>0
From 1 x>|Y|
hence X is positive ..so (x+y) and (x-y) will be both positive...(x+y)(x-y)>0 ..sufficient
From 2
|x|>y
So (x+y)(x-y)>0 ..sufficient
Ans option D
"If you don't know where you are going, any road will get you there."
Lewis Carroll
Lewis Carroll
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ballubalraj
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Another way to solve it:
Square of any positive or negative number is always positive. So irrespective of the sign of x and y, as long as x > y (leaving the sign), x^2 - y^2 will always be > 0.
As both the statements say that x > y (leaving the sign part), both statements alone are sufficient.
Answer: D
Square of any positive or negative number is always positive. So irrespective of the sign of x and y, as long as x > y (leaving the sign), x^2 - y^2 will always be > 0.
As both the statements say that x > y (leaving the sign part), both statements alone are sufficient.
Answer: D
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November Rain
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Hi,
I agree that statment 1 is sufficient, but i am not sure about 2.
take X = -3 and Y = -4
This means that |x|>y, but, x^2 - y^2 < 0
I agree that statment 1 is sufficient, but i am not sure about 2.
take X = -3 and Y = -4
This means that |x|>y, but, x^2 - y^2 < 0
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ballubalraj
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I guess November Rain is correct. GMAT always tricks us with simple looking but tricky questions - ineuqalities and modes are probably the best examples.
So the answer should be A.
Any thoughts?
So the answer should be A.
Any thoughts?
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nakul_anand
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Yep...I think that the answer should be A
November Rain's values - -3 and -4 prove that a^2-b^2 can be less than 0.
November Rain's values - -3 and -4 prove that a^2-b^2 can be less than 0.
