OG - 105

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OG - 105

by AleksandrM » Tue Jun 24, 2008 6:34 pm
Is |x| = y - z?

(1) x + y = z

(2) x < 0

My approach is different from that of the book:

x = z - y or - x = y - z, so we need to know the sign of x

if x < 0, then -(-x) = y - z or |x| = y - z.

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by anshul265 » Tue Jun 24, 2008 7:33 pm
I solved it the same way. Answer should be C.

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by ksh » Wed Jun 25, 2008 3:11 am
Stm 1.
x=z-y
-x=y-z
Now |x| may be -x or x

stmt 1 is suff.
Stm2. Insuff

IMO A

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by AleksandrM » Wed Jun 25, 2008 9:27 am
ksh,

Your equation is contingent on what the sign of x is.

OA is C. Thank you both.