18
15 + 3 - 6 / 2 * 6 = 15 + 3 - 3 * 6 = 15 + 3 - 18 = 18 - 18 = 0
(18/3) + 6 -(2 x 4) = 4
3 + 3 = 6 6 x 3 = 18 18 - 3 = 15 15 + 3 = 18
-9
Zero
-6 x -3 = 18 + (-6) = 12
That factors to (x - 3)(x + 6)
3 + 6 - 2 + 14 - 3 + 2 = 20
3 minus 3/18 is 2 5/6
(x - 3)(x^2 + 6)
minus 6, plus 3, minus 6, plus 3...