解:解方程, 此方程的解为x = 12/7 x - 3(1 - 2x)= 9 x - 3 × 1 + 3 × 2x = 9 x - 3 + 6x = 9 7x - 3 = 9 7x = 9 + 3 7x = 12 x = 12 ÷ 7 x = 12 × 1/7 ∴x = 12/7 答:此方程的解为x = 12/7