I would "selectively" choose x values that would cancel the 2 of the denominator. For example, let x = 2 so that (3/2)*2 = 3 and that + 4 = 7. Then a four would work. (3/2)*4 = 6 and that + 4 = 10. Then choose -2 for x and -4 for x and you get the bottom half of the line, etc.
