If 6xy = x2y + 9y, what is the value of xy?
(1) x = -2
(2) x < 0
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Value of XY
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papgust
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6xy = x^2 * y + 9y
x^2 * y - 6xy + 9y = 0
y*(x^2-6x+9)=0
y=0 or x=3
1) x=-2. I don't find any relevance or any use of this statement. Since we know that y can only be 0, then xy will also be 0.
Sufficient.
2) x<0. Same reason as statement 1. xy will only be 0.
Sufficient.
Answer: D
I somehow don't like this problem. Thought it would be challenging before reading it, but i feel that this problem is missing some crux.
x^2 * y - 6xy + 9y = 0
y*(x^2-6x+9)=0
y=0 or x=3
1) x=-2. I don't find any relevance or any use of this statement. Since we know that y can only be 0, then xy will also be 0.
Sufficient.
2) x<0. Same reason as statement 1. xy will only be 0.
Sufficient.
Answer: D
I somehow don't like this problem. Thought it would be challenging before reading it, but i feel that this problem is missing some crux.
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vzzai
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IMO this question is not framed correctly. Please let me know if my understanding is wrong.
I solved in this method.
6xy=x^2y+9y
6xy=y(x^2+9)
6x=x^2+9
x^2-6x+9 = 0
x=3
rephrased the question to, If x=3, what is xy?
So, to solve xy we need the value of y.
Both statements give value of x but not y. So, I went for E.
Please provide explanation. Thank you so much.
I solved in this method.
6xy=x^2y+9y
6xy=y(x^2+9)
6x=x^2+9
x^2-6x+9 = 0
x=3
rephrased the question to, If x=3, what is xy?
So, to solve xy we need the value of y.
Both statements give value of x but not y. So, I went for E.
Please provide explanation. Thank you so much.
Thank you,
Vj
Vj
