Ответ: \[17 - 12 \cdot (x + 1) = 9 - 3x\] \[17 - 12x - 12 = 9 - 3x\] \[- 12x + 3x = 9 - 5\] \[- 9x = 4\] \[x = - \frac{4}{9}.\]