Is the opposite of an opposite number always going to be positive?

No, the opposite of an opposite will not always be positive. the opposite of -4 is 4, and the opposite of that is -4, so the opposite of the opposite of the number -4 is -4, which is not positive. On the other hand, it CAN be positive. The opposite of 7 is -7, and opposite of that is 7, which is positive.

Yes it is because if you reflect for a min, the opposite (which is a negative) of the opposite is always going to be a positive.