If x is not equal to y
(x-y)/ (x+y) > 1 ?
1) x>0
2)y<0
inequality
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- cubicle_bound_misfit
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IMO it is B.
Please let me know OA.
my approach.
We gotta prove is x-y>x+y ?
i.e. is -y>y
stmt 2 SUFF.
regards,
Please let me know OA.
my approach.
We gotta prove is x-y>x+y ?
i.e. is -y>y
stmt 2 SUFF.
regards,
Cubicle Bound Misfit
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When you multiply an inequality, you need to be certain of the sign. If x+y is negative, the sign is reversed.... so I don't think you can do this since we can't be sure of the sign.cubicle_bound_misfit wrote:We gotta prove is x-y>x+y
Would be interested in the OA though. I need a methodical way of working this one out!
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I think "cubicle_bound_misfit" i correct in solving the eqn.
The eqn can be reduced to 2y < 0 or y <0
so answer shld be B .
Pls correct me if I am going fundamentally wrong in soloving the equation.
The eqn can be reduced to 2y < 0 or y <0
so answer shld be B .
Pls correct me if I am going fundamentally wrong in soloving the equation.
I think jsl brings up a good point to remember about signs and direction of inequality when cross multiplying. But I also agree with some of the other posters and think B is sufficient.
To simplify the "rephrase" of the questions stem asks: "Is y>0 or is y<0?" (factoring in that the unknown signs can flip the inequality)
1) tells us nothing about y - insufficient
2) tells us y<0 - SUFFICIENT
To simplify the "rephrase" of the questions stem asks: "Is y>0 or is y<0?" (factoring in that the unknown signs can flip the inequality)
1) tells us nothing about y - insufficient
2) tells us y<0 - SUFFICIENT
- cubicle_bound_misfit
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hi JSL,
the way I tried it
if x-y/x+y is > 1 then both denominator and numerator both has to be either greater than zero or less than zero.
in both the cases if you pick numbers , multiplying expression by denominator does not invert ineqalities.
Please let me know if I am wrong and what's the OA?
regards,
the way I tried it
if x-y/x+y is > 1 then both denominator and numerator both has to be either greater than zero or less than zero.
in both the cases if you pick numbers , multiplying expression by denominator does not invert ineqalities.
Please let me know if I am wrong and what's the OA?
regards,
Cubicle Bound Misfit
Actually I'm rethinking this going back through it with a common sense check by picking some numbers... maybe I've overthought the problem by trying to solve it with algebra
Maybe 2) y<0 isn't so sufficient after all.
Consider x=3, y=-1
Stem eqn will equal 2 which is a "YES" answer
Consider x=3, y=-4
Stem eqn will equal -1 which is a "NO" answer
Statement 1) suffers the same conclusion, as well as the statements together.
Could E be the answer after all?
Maybe 2) y<0 isn't so sufficient after all.
Consider x=3, y=-1
Stem eqn will equal 2 which is a "YES" answer
Consider x=3, y=-4
Stem eqn will equal -1 which is a "NO" answer
Statement 1) suffers the same conclusion, as well as the statements together.
Could E be the answer after all?