If X is positive, is X > 3.
Statement 1: (X-1)^2 > 4
Statement 2: (X-2)^2 > 9
The given information that X is positive is necessary to solve this problem correctly.
Statement 1:
(X-1)^2 > 4 = X-1 > 2 or X - 1 < -2, so x > 3 or X < -1. However we know that X has to be positive, so ignore the possibility that X < -1. So we know that X > 3. (Sufficient)
Statement 2:
(X-2)^2 > 9 = X-2 > 3 or X - 2 < -3, so X > 5 or X < -1. However, once again, we know that X has to be positive, so ignore the possibility that X < -1. So we know that X > 5 (and therefore X > 3). (Sufficient).
Both statements are sufficient, so the answer is D.
Last edited by
Toph@GMAT_REBOOT on Fri Nov 28, 2008 12:14 pm, edited 1 time in total.