Is M<0?

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Is M<0?

by NandishSS » Fri Apr 06, 2018 5:23 am
Is M<0?

(1) -M = |-M|
(2) M^2 = 9

OA: C

(2) M^2 = 9 m= +/- 3

How (1) is not suff

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by GMATGuruNY » Fri Apr 06, 2018 5:31 am
NandishSS wrote:Is M<0?

(1) -M = |-M|
(2) M^2 = 9
Statement 1:
It's possible that M=0, in which case the answer to the question stem is NO.
It's possible that M=-1 in which case the answer to the question stem is YES.
INSUFFICIENT.

Statement 2:
If M=3, then the answer to the question stem is NO.
If M=-3, then the answer to the question stem is YES.

Statements combined:
Only M=-3 satisfies both statements.
Thus, the answer to the question stem is YES.
SUFFICIENT.

The correct answer is C.
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