If xy ≠ 0, could y be expressed as -2/x? :: Manhattan GMAT Forums

Posted: Sat Jun 21, 2008 12:47 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"

Posted: Fri Jun 27, 2008 4:02 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.

Posted: Fri Jun 27, 2008 7:29 pm

Thanks Rey!

Posted: Wed Sep 03, 2008 6:04 pm

we're glad to help!