Explanation

The question is asking us whether the following is true:



The fact that x is an integer may or may not be important. Let's turn to the data statements, looking at them separately first. (If we were pressed for time on this question, we could judge Statement (2) insufficient fairly quickly, since it says not a thing that bears on y and z, and we'd be down to three answer choices for a guess.)

Statement (1) gives us values for y and z that we can plug into our expression of interest:



Expanding the right side:



At this point, we could try to compare the first terms and the second terms individually, or get the 5's on one side and the 3's on the other. We find the latter route simpler:



Now we can test a few cases. Take the case :







The inequality is true for . Moreover, looking at what's going on here, we think the difference is going to get bigger and bigger for larger values of x (and we have to worry about only positive integers for x). Higher values of x will increasingly amplify the fact that 5 is a higher base than 3. Moreover, the first term on each side will grow much faster than the second term, so the difference expressed on the right side will get big fast. We'll try :





The left side is only about 20, whereas the right is a couple hundred. We can convince ourselves that the gap will only grow with larger x. Statement (1) is sufficient. And as we've noted parenthetically, Statement (2) is insufficient.

The correct answer is (A).