13  If X, Y, and Z are positive integers, is Y>X?

(1)   Y^2=XZ

(2)   Z-X>0

l        Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient

l        Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient

l        BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

l        EACH statement ALONE is sufficient

l        Statements (1) and (2) TOGETHER are NOT sufficient

Answer C

请问各位,怎么由两个条件得出Y>X啊

Z>X  XZ=Y^2

说明了 X<Y<Z

Y在X，Z之间

所以 选C