| 4 | x | − | 3 | ( | 19 | − | x | ) | = | 6 | x | − | 7 | ( | 9 | − | x | ) |
| 方程左边 = | 4 | x | − | 3 | × | 19 | + | 3 | x |
| = | 4 | x | − | 57 | + | 3 | x |
| = | 7 | x | − | 57 |
| 7 | x | − | 57 | = | 6 | x | − | 7 | ( | 9 | − | x | ) |
| 方程右边 = | 6 | x | − | 7 | × | 9 | + | 7 | x |
| = | 6 | x | − | 63 | + | 7 | x |
| = | 13 | x | − | 63 |
| 7 | x | − | 57 | = | 13 | x | − | 63 |
| 7 | x | − | 13 | x | = | - | 63 | + | 57 |
| - | 6 | x | = | - | 63 | + | 57 |
| - | 6 | x | = | - | 6 |
| 6 | = | 6 | x |
| 6 | x | = | 6 |
| x | = | 6 | ÷ | 6 |
| = | 6 | × | 1 6 |
| = | 1 | × | 1 |
| x | = | 1 |