| x | − | ( | x | − | 723 10 | ) | × | 13 100 | − | 723 10 | = | 3 20 | x |
| 方程左边 = | x | − | x | × | 13 100 | + | 723 10 | × | 13 100 | − | 723 10 |
| = | x | − | x | × | 13 100 | + | 9399 1000 | − | 723 10 |
| = | 87 100 | x | − | 62901 1000 |
87 100 | x | − | 62901 1000 | = | 3 20 | x |
87 100 | x | − | 3 20 | x | = | 62901 1000 |
18 25 | x | = | 62901 1000 |
| x | = | 62901 1000 | ÷ | 18 25 |
| = | 62901 1000 | × | 25 18 |
| = | 6989 40 | × | 1 2 |
| x | = | 6989 80 |
| x | = | 87.3625 |