Is x a negative number?
(1) x^2 is a positive number
(2) x · |y| is not a positive number
please provide explanation. OA to follow after a few threads. Thanks.
Negative X?
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Statement Ijust_do_it wrote:Is x a negative number?
(1) x^2 is a positive number
(2) x · |y| is not a positive number
please provide explanation. OA to follow after a few threads. Thanks.
x^2 always will be positive. x can be negative or positive. Insufficient.
Statement II
x* lyl is not a positive, this means it could be 0 or negative. Because 0 is neither positive nor negative. Insufficient.
Combining I & II
if x^2 is positive, this means x is a non zero number. x*lyl will be negative. Therefore, x is negative. Sufficient.
Hence C.
OA?
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E for me ,
1) X^2 is positive therefor x can be positive or negative
2) x.|y| is not a postive number , thus x can be 0 , -ve or +ve
it can be positive when |y| = 0,
combining X CAN BE +VE , -VE , thus E
1) X^2 is positive therefor x can be positive or negative
2) x.|y| is not a postive number , thus x can be 0 , -ve or +ve
it can be positive when |y| = 0,
combining X CAN BE +VE , -VE , thus E
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(1) x can be anything except 0, so it could be + or -... insufficient.just_do_it wrote:Is x a negative number?
(1) x^2 is a positive number
(2) x · |y| is not a positive number
(2) x*|y| is either negative or 0.
if y = 0, then x * |0| = 0 no matter what x is.
Therefore, if y = 0, x could be any number... insufficient.
Together: if y=0, then x could be + or -... still insufficient, choose (E).
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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Stuart Kovinsky wrote:(1) x can be anything except 0, so it could be + or -... insufficient.just_do_it wrote:Is x a negative number?
(1) x^2 is a positive number
(2) x · |y| is not a positive number
(2) x*|y| is either negative or 0.
if y = 0, then x * |0| = 0 no matter what x is.
Therefore, if y = 0, x could be any number... insufficient.
Together: if y=0, then x could be + or -... still insufficient, choose (E).
In (2), possibility that x*|y| is negative is not discussed. Can anyone elaborate it
I also have one question, what difference does mod make to the entire question..what would be the solution if b would have been just x*y is not positive
Thanks for your time and efforts !
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In (2), possibility that x*|y| is negative is not discussed. Can anyone elaborate it
I also have one question, what difference does mod make to the entire question..what would be the solution if b would have been just x*y is not positive
Thanks for your time and efforts !
You are right; not positive means it could include 0 and negtaive. What Stuart pointed out is if its 0 (not positive) i.e. |y| is 0 then x could be negative or positive and still the product would not be positive. We dont have to get in to the realm of the product being negative
If it was x.y is not positive then still y could be 0(so we cant tell for sure if x is postive or negative). Still the answer would be E)