xunil56 wrote: IF xyz > 0 then, is x > 0?
1) xy > 0
2) xz > 0
Can you explain why OA is C?
xyz > 0 x>0?
statement (1)
xy>0
x could be negative, then y has to be negative
x could be positive, then y has to be positive.
Insufficient.
statement (2)
xz>0
same as above we can have both the cases of positive and negative.
Insufficient.
combining (1) & (2)
xz>0
xy>0
if x is negative, y and z both have to be negative, but then xyz> 0 will not hold true.
Therefore, x is positive. Sufficient.
Thus, C is the answer.

















