Absolute Value confusion

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Absolute Value confusion

by Gurpinder » Thu Sep 29, 2011 8:23 am
Not quite sure about (1).

(1) basically says that x = -x and plugging that into the question, = x

The book says that the value of an absolute value can be 0 or x? Doesn't make sense!
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by rohit_gmat » Thu Sep 29, 2011 8:43 am
Gurpinder wrote:Not quite sure about (1).

(1) basically says that x = -x and plugging that into the question, = x

The book says that the value of an absolute value can be 0 or x? Doesn't make sense!
hi...

i think stmnt 1 is basically sayin tht x is a negative number... e.g. -5 = - |-5| = - (+5) = -5
or maybe zero.... (-0 = 0) .... but since it can be any number, we cant find the value of |x|...
INSUFF

stmnt 2.. says x^2 = 4 ... so x = +2 or -2 .. but |x| = 2 ONLY ... SUFF

IMO B

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by Gurpinder » Thu Sep 29, 2011 8:47 am
ahhh

so when a question asks for a value it has to be a SINGLE NUMERICAL value. it can't be a variable OR multiple values.

correct?
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by Brent@GMATPrepNow » Fri Sep 30, 2011 4:15 am
Gurpinder wrote:ahhh

so when a question asks for a value it has to be a SINGLE NUMERICAL value. it can't be a variable OR multiple values.

correct?
Exactly. It must be a single numerical value.

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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