y in terms of x

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y in terms of x

by vishubn » Thu Oct 23, 2008 10:03 am
If xy ≠ 0 and x^2 * y^2 – xy = 6, which of the following could be y in terms of x?
I. 1/(2x)
II. – 2/x
III. 3/x
A. I only
B. II only
C. I and II
D. I and III
E. II and III

OA E

Vishu
Last edited by vishubn on Thu Oct 23, 2008 10:18 am, edited 2 times in total.

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by amitabhprasad » Thu Oct 23, 2008 10:13 am
Is the answer "E"

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by vishubn » Thu Oct 23, 2008 10:18 am
ya ! wat was the approach !

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by dmateer25 » Thu Oct 23, 2008 10:27 am
X^2*Y^2 - XY = 6

X^2*Y^2 - XY - 6 = 0

(XY - 3) (XY + 2) = 0

XY - 3 = 0 || XY + 2 = 0

Y = 3/X || Y = -2/X

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by cramya » Thu Oct 23, 2008 1:56 pm
I did it slightly differently


I substituted y as 1/2x, -2/x and 3/x and ended up getting 6 for II and III

Hence E)

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by cramya » Thu Oct 23, 2008 1:58 pm
dmateer's approach is good too!

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by raunekk » Fri Oct 24, 2008 1:45 am
its simple factorization...

as dmateer25 as shown

E for me 2

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by rohangupta83 » Fri Oct 24, 2008 2:23 am
E for me too