| ( | 60 | − | 2 | x | ) | × | 80 | − | 4 | x | = | 50 | × | 60 |
| 方程左边 = | 60 | × | 80 | − | 2 | x | × | 80 | − | 4 | x |
| = | 4800 | − | 160 | x | − | 4 | x |
| = | 4800 | − | 164 | x |
| 4800 | − | 164 | x | = | 50 | × | 60 |
| 方程右边 = | 3000 |
| 4800 | − | 164 | x | = | 3000 |
| - | 164 | x | = | 3000 | − | 4800 |
| - | 164 | x | = | - | 1800 |
| 1800 | = | 164 | x |
| 164 | x | = | 1800 |
| x | = | 1800 | ÷ | 164 |
| = | 1800 | × | 1 164 |
| = | 450 | × | 1 41 |
| x | = | 450 41 |
| x | = | 10.97561 |