| ( | 6 | − | 3 | x | ) | ÷ | 3 | − | ( | 5 | x | + | 12 | ) | ÷ | 4 | = | - | 1 |
| 方程左边 = | 6 | × | 1 3 | − | 3 | x | × | 1 3 | − | ( | 5 | x | + | 12 | ) | × | 1 4 |
| = | 2 | − | 1 | x | − | ( | 5 | x | + | 12 | ) | × | 1 4 |
| = | 2 | − | 1 | x | − | 5 | x | × | 1 4 | − | 12 | × | 1 4 |
| = | 2 | − | 1 | x | − | 5 4 | x | − | 3 |
| = | - | 1 | − | 9 4 | x |
| - | 1 | − | 9 4 | x | = | - | 1 |
| - | 9 4 | x | = | - | 1 | + | 1 |
| - | 9 4 | x | = | - | 0 |
| 0 | = | 9 4 | x |
9 4 | x | = | 0 |
| x | = | 0 | ÷ | 9 4 |
| = | 0 | × | 4 9 |
| x | = | 0 |