Final answer:
The opposite of a positive number is greater than the number, the opposite of a negative number is less than the number, and the opposite of zero is equal to zero.
Step-by-step explanation:
The question is asking about the values of a for which the opposite of a is greater than, less than, or equal to a.
If we consider the real numbers, the opposite of a positive number is always negative and greater than a. So, for a positive value of a, the opposite of a is greater than a.
On the other hand, the opposite of a negative number is always positive and less than a. So, for a negative value of a, the opposite of a is less than a.
Lastly, the opposite of zero is still zero, so it is equal to a.