IMO it's: B - 2 alone is sufficient.blaster wrote:Is x > y?
(1) x^2 > y
(2) x - |y| > 0
In 1, x & y can be any value. ex. x= -2 and y = 1. x^2 > 1 but x > y is not true. Insufficient.
In 2, x -|y| > 0 is sufficient.
DS , module
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Source: Beat The GMAT — Data Sufficiency |
In 1, x & y can be any value. ex. x= -2 and y = 1. x^2 > 1 but x > y is not true. Insufficient.
In 2, x -|y| > 0 is sufficient.
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Patrick_GMATFix
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Hello blaster,
(1) is not sufficient. If x = 5, y could be 7 (x would be greater0 but y could also be 0 (x would not be greater). We don't know whether x > y.
(2) is sufficient. It tells us that x is greater than |y|, so x must be positive.
-->If y is also positive, then y=|y| and because x > |y|, it is guaranteed that x > y.
-->On the other hand, if y is negative, then x >y (since x is positive)
either way, x>y, so (2) is sufficient. the answer is B
Hope that helped,
-Patrick
(1) is not sufficient. If x = 5, y could be 7 (x would be greater0 but y could also be 0 (x would not be greater). We don't know whether x > y.
(2) is sufficient. It tells us that x is greater than |y|, so x must be positive.
-->If y is also positive, then y=|y| and because x > |y|, it is guaranteed that x > y.
-->On the other hand, if y is negative, then x >y (since x is positive)
either way, x>y, so (2) is sufficient. the answer is B
Hope that helped,
-Patrick
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jonathan123456
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Testluv
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Because absolute value is always positive or zero:kvcpk wrote:Hi Patrick,Patrick_GMATFix wrote:Hello blaster,
-->On the other hand, if y is negative, then x >y (since x is positive)
-Patrick
How do we know that x is positive?
x>|y|
x>pos or zero
If x is greater than pos or zero, then x is definitely positive.
Suppose |z| = w
We know the left hand side must be positive or zero. We know the left hand side must equal the right hand side. Thus, w is positive or zero.
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raunakrajan
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First Statement defi doesnt qualify to be correct.
IMO, the second statement states x-!y!>0, this x has to be positive. if X is not positive x - mod y wouldnt be greater than 0
hence we can conclude that B is sufficient
IMO, the second statement states x-!y!>0, this x has to be positive. if X is not positive x - mod y wouldnt be greater than 0
hence we can conclude that B is sufficient
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kvcpk
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Got it now.. thanks!!Testluv wrote:Because absolute value is always positive or zero:kvcpk wrote:Hi Patrick,Patrick_GMATFix wrote:Hello blaster,
-->On the other hand, if y is negative, then x >y (since x is positive)
-Patrick
How do we know that x is positive?
x>|y|
x>pos or zero
If x is greater than pos or zero, then x is definitely positive.
Suppose |z| = w
We know the left hand side must be positive or zero. We know the left hand side must equal the right hand side. Thus, w is positive or zero.
