My answer is D
x^2y^2=18 - 3xy
x^2y^2+3xy -18 = 0
Making it an equation (think of xy as one term)
(xy+6)(xy-3) = 0
which gives xy= -6 or xy= 3
Since the stem says that x and y are positive, we go with 3
replace xy by 3 in the second part of the question and you get : x^2y^2=18 - 3 (3)
x^2y^2=9
x^2=9/y^2
What do you think of the approach?
MGMAT - 4 those who love algebra ))
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4meonly
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I think your approach is correct.x^2y^2+3xy -18 = 0
(xy+6)(xy-3) = 0
I overlooked mentioned above equation but from
xy(xy+3)=18
concluded that xy=3 and than the same as yours
unfortunately, I dont know OA but will get it soon
