{x | 2-x = 4 and x is a fraction}
The answer is -2, right? I'm only asking because the question before it asks the same thing and stipulates that x must be an integer. I have a feeling there is a trick somewhere.
If we assume that "fraction" here is a synonym of a "rational number," then the answer is {-2}, i.e., a set. However, it seems that "fraction" here means "a rational number that is not an integer." In this case, the answer is the empty set.