DS / X > 3 ?

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DS / X > 3 ?

by Xbond » Mon Oct 19, 2009 1:07 pm
Hi there,

Could you explain to me how to resolve this DS. For each statement, I found 2 results. So, I selected E but it is wrong.

if x is positive, is X > 3 ?

(1) (x-1)² > 4

(2) (x-2)² > 9




[spoiler]
OA is D[/spoiler]
Source: — Data Sufficiency |

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by grockit_jake » Mon Oct 19, 2009 3:06 pm
The key here is the requirement: "If x is positive".

While you may have 2 solutions for x in each of the equations, only one of those solutions is positive.

(1) x > 3 , x < -1

(2) x > 5 , x < -1

If x>5 it must also be >3.
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by Xbond » Mon Oct 19, 2009 8:10 pm
ok, if I well understood your answer is B
But the OA is D. It is the reason why I lost

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by Talkativetree » Mon Oct 19, 2009 8:18 pm
his answer was D.

"if x is positive" knocks out both of the negative scenarios in 1 and 2.

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by Xbond » Mon Oct 19, 2009 8:28 pm
many thks
I understood now