Hi,
I have a conceptual question about variables. In the GMAT, "x" (or, "y", whatever) or represents a unique unknown number, right?
For example:
If they say x^2=4, what is the value of x? Then the possible solutions are 2 or -2. But because x represents an unknown number can be ONLY one of those solutions, right? So, in this case, we don't know what the value of x is. We cannot answer the question.
Another example:
If they say |x-2|>4, is x>5? Then again we have two possible solutions x>6 or x<-2. Again, we cannot answer the question because or x>6 OR x>-2. CANNOT BE BOTH, right?
In summary, the possible solutions of a variable are the possible values of that variable, but ONLY one of them is its true value. The possible solutios are NOT the values that variable have.

Sorry for this dumb question, but the other day I read a different concept of variable (very different from what I learned in high school) and that confused me. :s That book said that a variable is something that can be replaced for any number of a set of numbers. :s