GMATprep DS question

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GMATprep DS question

by mlane25269 » Sat Jun 21, 2008 12:52 pm
How did they get this answer?
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by atlantic » Sat Jun 21, 2008 2:24 pm
Hey mlane,

Often in GMAT difficult things are easier than they appear.

Let xy=t

(1) t^2+2t+1=0, using the quadratic formula, we get t=xy=-1, so SUFF

(2) we get nothing at all, so INSUFF

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by mlane25269 » Tue Jun 24, 2008 11:31 am
ok got it! that makes perfect sense! thanks, atlantic! :-)