Math questions from any Manhattan Prep GMAT Computer Adaptive Test.
Rahul
 
 

If xy ≠ 0, could y be expressed as -2/x?

by Rahul Sat Jun 21, 2008 1:47 pm

Source: Manhattan Quest for 750: Advanced Quant Homework Bank
If xy ≠ 0, could y be expressed as -2/x?

(1) x2y2 - xy = 6

(2) y ≠ 3/x


I understand for the above DS question answer is A. For A we get ans as y=3/x or y =-2/x. Is it because the question states could be expressed as -2/x?

What is question had stated is y=-2/x? In this case would the answer be "C"
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by rfernandez Fri Jun 27, 2008 5:02 am

I agree with that. The relation x^2y^2 - xy = 6 is a non-function whereas y = -2/x is a function, so the two are not simply interchangeable. The wording of the question ("could") is an important distinction.
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by Guest Fri Jun 27, 2008 8:29 pm

Thanks Rey!
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by StaceyKoprince Wed Sep 03, 2008 7:04 pm

we're glad to help!
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