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If zy<xy<0, is xz+x=z [#permalink]
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26 Mar 2009, 10:53
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I think this was posted before but I can't find it. Can you please explain your answers: If zy0 == Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.



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Re: DS GMAT Prep  Inequalities [#permalink]
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26 Mar 2009, 12:48
If zy<xy<0, is xz+x=z 1) z<x 2) y>0 we will be able to solve xz+x=z if we get to know the signs of x and Z. 1) z<x , this just rephrases the given information which is not useful. No infrmation is specified regarding y , so we can not deduce the sign of x or z. INSUFFICIENT. 2)y>0 given : zy<xy<0 if y > 0 , x and z must be less than 0 also z<x<0. now we can answer the inequality . SUFFICIENT. Answer : B
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Re: DS GMAT Prep  Inequalities [#permalink]
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26 Mar 2009, 13:44
I agree  Statement 2 is sufficient  so the answer is B.
What is the OA?



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Re: DS GMAT Prep  Inequalities [#permalink]
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26 Mar 2009, 14:13
Sorry guys, OA is D.



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Re: DS GMAT Prep  Inequalities [#permalink]
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26 Mar 2009, 14:28
Accountant wrote: I think this was posted before but I can't find it. Can you please explain your answers:
If zy<xy<0, is xz+x=z
1) z<x 2) y>0 from given condition zy<xy from (1), z<x > y is positive > z and x, both are negative and z < x. So, simplifying the equation: LHS = xz+x = xz + (x) = xzx = z RHS = z = z (since z<0) which implies, LHS = RHS , hence (1) is sufficient from (2) , y> 0 > z <0, x<0. Noe proceed the same way as above, that will give us a solution. Both (1) and (2) are sufficient separately. Therefore, answer is (D).
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Re: DS GMAT Prep  Inequalities [#permalink]
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26 Mar 2009, 19:01
krishan wrote: Accountant wrote: I think this was posted before but I can't find it. Can you please explain your answers:
If zy<xy<0, is xz+x=z
1) z<x 2) y>0 from given condition zy<xy from (1), z<x > y is positive > z and x, both are negative and z < x. So, simplifying the equation: LHS = xz+x = xz + (x) = xzx = z RHS = z = z (since z<0) which implies, LHS = RHS , hence (1) is sufficient from (2) , y> 0 > z <0, x<0. Noe proceed the same way as above, that will give us a solution. Both (1) and (2) are sufficient separately. Therefore, answer is (D). Agree 100% You can rewrite the expression in the question as zyxy<0 > y(zx) < 0. This leads to two options; either y<0 and zx>0 or y>0 and zx<0 From stat 1, you know z<x , so just quickly picking numbers, you see that the equality in question never holds. From stat 2, you know z<x, and same approach as above gives the same result



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Re: DS GMAT Prep  Inequalities [#permalink]
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27 Mar 2009, 03:18
I get it now. Thanks pmenon. Answer : D == Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.
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Re: DS GMAT Prep  Inequalities
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