Modulus-quick one

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Modulus-quick one

by selango » Fri Oct 08, 2010 8:14 am
What is the value of |x| ?

(1) x = |x|

(2) x^2 = 9



[spoiler]Source: grockit[/spoiler]
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by sanabk » Fri Oct 08, 2010 8:28 am

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by diebeatsthegmat » Fri Oct 08, 2010 2:47 pm
selango wrote:What is the value of |x| ?

(1) x = |x|

(2) x^2 = 9



[spoiler]Source: grockit[/spoiler]
from statement 2. x^2=9 so x =+/-3....insufficient
statement x=|x| thus x must be positive since |3|=3 and = 3 but |-3|=3#-3 insufficient
from 1+2 so x =3

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by Testluv » Fri Oct 08, 2010 8:33 pm
(1) is clearly insufficient as there is no value. Eliminate A and D.

(2) tells us that x is 3 or -3. The absolute value of both of these numbers is 3. Thus, (2) is sufficient by itself.

The answer is B.
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by selango » Fri Oct 08, 2010 10:07 pm
OA B
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by diebeatsthegmat » Fri Oct 08, 2010 10:25 pm
Testluv wrote:(1) is clearly insufficient as there is no value. Eliminate A and D.

(2) tells us that x is 3 or -3. The absolute value of both of these numbers is 3. Thus, (2) is sufficient by itself.

The answer is B.
ohh yeah, i forgot that it just wanted to know what \X\ is, not what x is....
thanks

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by Yanat » Sat Oct 09, 2010 12:25 am
IMO it is B.