In this DS question, you might find that 'rewriting' the question makes it easier to answer. Either way, you'll find that a combination of logic, Number Properties and TESTing VALUES will come in handy.
We're asked if 2X - 3Y < X^3. You can 'rewrite' the question to ask if 2X < X^3 + 3Y. Either way, this is a YES/NO question.
Fact 1: 2X - 3Y = -2
Here, the 'original' version of the question is probably easier to answer, since we now have a value that we can 'substitute' in for (2X - 3Y)....
The question now asks.....
Is -2 < X^3?
The answer to this question depends completely on the value of X.
X = 0, then the answer to the question is YES
X = -2, then the answer to the question is NO
Fact 1 is SUFFICIENT
Fact 2: X > 2 and Y > 0
With this Fact, the 'rewritten' version of the question is probably easier to answer.
Since we know that X > 2......2X will ALWAYS be < X^3. We also know that Y > 0, so (X^3 + 3Y) will get larger as Y gets larger. This all serves as evidence that....
2X is ALWAYS < X^3 + 3Y.
Fact 2 is SUFFICIENT
GMAT assassins arne't born, they're made,
EMPOWERgmat GMAT Club Page, Study Plans, & Discounts