Respuesta :

Start with |1x - 12| < 15.  Add 12 to both sides.  Then |1x - 12 + 12| < 15 + 12

Simplifying, |x| < 27.  Then the two solutions are x < 27 and x > -27.  In words, the solution set is the set of all x greater than -27 and less than +27.