Answer:
Hi!
-When you say opposite of a number, do you mean multiplying the number by (-1)? If so, then it will sometimes be greater than itself. Like for example, -5. The opposite of -5 is 5. Because -5(-1) is 5.
-But if we have a positive number to begin with like 9, it would be less than itself because 9(-1) is -9.
Hope this gave a brief explanation and helped in some way.