however, even though this way of expressing S is apparently simpler, it does not tell us that we are interested in the solutions of an equation. The absolute value Irl of a real number x is x if x 20; while lxl x if x 0. Therefore is the set of all real numbers having absolute value 2, that is, T 12 2). In the sets S and T that we have just described, we understand that "x" refers to a real number x. If