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Source: — Data Sufficiency |

by mehravikas » Tue Jul 14, 2009 10:56 pm
This question has been already posted....

Statement 1 - Pick some values for x

x = 7 -> square root (7 - 3)^2 = 3 - 7 L.H.S <> R.H.S
x = -4 -> square root (-4 - 3)^2 = 3 - (-4) L.H.S = R.H.S

Hence insufficient

statement 2 - for -x |x| to be greater than 0, x has to be negative.

For negative values of x you will always get square root (x - 3)^2 = 3 - x

Answer: B
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by real2008 » Wed Jul 15, 2009 2:23 am
mehravikas wrote:This question has been already posted....

Statement 1 - Pick some values for x

x = 7 -> square root (7 - 3)^2 = 3 - 7 L.H.S <> R.H.S
x = -4 -> square root (-4 - 3)^2 = 3 - (-4) L.H.S = R.H.S

Hence insufficient

statement 2 - for -x |x| to be greater than 0, x has to be negative.

For negative values of x you will always get square root (x - 3)^2 = 3 - x

Answer: B
sorry! I don't get ur reasoning for statement 2 to be sufficient to answer the qn. please explain.....
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by sk8ternite » Wed Jul 15, 2009 7:52 am
statement 2 states that -xlxl>0, so lxl will always be positive, therefore, x needs to be negative in order for the statement to be true. If you plug in any negative value in the equation above, it works, the equation simplified is essentially, (x-3)=3-x
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