Evaluate x

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Evaluate x

by nikhilsrl » Sun Feb 06, 2011 4:29 am
if x > 0, what is x?

1. x > 5
2. 40 - ( x )squared = 4

I am not sure where this question is from. I had noted this down since I got it wrong first time. As per my notes answer is C.

But I am wondering why not B.

If we evaluate (2) we will get x = +6 or x = -6. Since the question itself says x > 0, x = +6 will be the value. Hence B.

Please clarify.
Source: — Data Sufficiency |

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by Anurag@Gurome » Sun Feb 06, 2011 5:06 am
(1) x > 5 does not imply any unique value of x. So, statement 1 is NOT SUFFICIENT.

(2) 40 - x^2 = 4 implies x^2 = 36 implies x = +6, -6.
Since it is given that x > 0 so x = 6
So, (2) is SUFFICIENT.

[spoiler]The correct answer is B.[/spoiler]
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