Answer :
The only possibility is -2 and zero, and I'm not really
all that sure that zero is considered an even number.
Tricky much! ;) Well, as we know, there is no even number going backwards of -2 except zero. So zero could be the possible answer. And -2, an integer could also be a possible answer. Hehehe some might say -1 + (-1) = -2. But that's not true.