Interesting GMATFix Problem-48

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Interesting GMATFix Problem-48

by arora007 » Sat Oct 09, 2010 2:02 am
If x is greater than 0, is root(-2xy + x^2 + y^2) > y-x ?
1) -y|y| > n^2
2) x>n>0
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by neerajkumar1_1 » Sat Oct 09, 2010 3:05 am
whats n ????

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by neerajkumar1_1 » Sat Oct 09, 2010 3:10 am
if i assume n as any integer or number...

from statement 1)
-y|y| > n^2

since RHS will be +ve , -y|y| will have to be +ve, hence y will be -ve

given eqn
root(-2xy + x^2 + y^2) > y-x
here the LHS always be +ve, since there is a root

now since y is -ve and x is >0 then RHS will always be -ve

so we have +ve> -ve
which is true...

thus sufficient...

statement2)
doesnt add anything...

Pick A...

whats OA??

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by arora007 » Sat Oct 09, 2010 11:17 am
OA is A, u've cracked it!!
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by diebeatsthegmat » Sat Oct 09, 2010 6:45 pm
arora007 wrote:OA is A, u've cracked it!!
we just need to know whether y is negative or positive to decide the answer,right? so pick A
A is the answer
however, why there is "n" here?
hey, honey, do you have its explaination? cos i think its weird!

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by Viktri » Wed Oct 13, 2010 10:26 pm
Data given:

formula can be simplified to x - y > y - x

We know X is positive

given this info, the answer depends on whether y is negative or positive (negative Y will increase the greater side and decrease the other side)

A) tells us Y is positive , suf

B) no info regarding Y, insuf

pick A
arora007 wrote:If x is greater than 0, is root(-2xy + x^2 + y^2) > y-x ?
1) -y|y| > n^2
2) x>n>0

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by ksundar » Thu Oct 14, 2010 6:34 pm
Solve the equations to get x>0 and x>y.

Statement 1: Y is negative which means x>y. Sufficient.
Statement 2: Clearly not sufficient or irrelevant.

Answer is A.