Gmat Prep Toughie

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Source: — Data Sufficiency |

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by Night reader » Sun Feb 20, 2011 1:07 am
y is s and x is r, now rewrite everything --> s=3r+2 OR 3r+2-s=0

st(1) BECOMES ridiculously simple ( 3r+2-s)(4r+9-s) = 0 is Not Sufficient, because we have also (4r+9-s) can be 0
st(2) (4r-6-s)(3r+2-s) =0; (3r+2-s) =0 ? Not Sufficient

Combined st(1&2): both ( 3r+2-s)(4r+9-s) = 0 AND (4r-6-s)(3r+2-s) =0 can be zero if one of common factors is 0 (zero). Only possible with the ( 3r+2-s) = 0 why not Sufficient?

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by btgyes » Sun Feb 20, 2011 1:13 am
Night reader wrote:y is s and x is r, now rewrite everything --> s=3r+2 OR 3r+2-s=0

st(1) BECOMES ridiculously simple ( 3r+2-s)(4r+9-s) = 0 is Not Sufficient, because we have also (4r+9-s) can be 0
st(2) (4r-6-s)(3r+2-s) =0; (3r+2-s) =0 ? Not Sufficient

Combined st(1&2): both ( 3r+2-s)(4r+9-s) = 0 AND (4r-6-s)(3r+2-s) =0 can be zero if one of common factors is 0 (zero). Only possible with the ( 3r+2-s) = 0 why not Sufficient?

IOM C
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Thanks Dude..

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by kanhaiya » Sun Feb 20, 2011 5:09 am
nice explanation.. thnx Night reader