| ( | x | − | 1 | ) | × | 50 | = | ( | x | + | 1 2 | ) | × | 60 |
| 方程左边 = | x | × | 50 | − | 1 | × | 50 |
| = | x | × | 50 | − | 50 |
| 50 | x | − | 50 | = | ( | x | + | 1 2 | ) | × | 60 |
| 方程右边 = | x | × | 60 | + | 1 2 | × | 60 |
| = | x | × | 60 | + | 30 |
| 50 | x | − | 50 | = | 60 | x | + | 30 |
| 50 | x | − | 60 | x | = | 30 | + | 50 |
| - | 10 | x | = | 30 | + | 50 |
| - | 10 | x | = | 80 |
| - | 80 | = | 10 | x |
| 10 | x | = | - | 80 |
| x | = | - | 80 | ÷ | 10 |
| = | - | 80 | × | 1 10 |
| = | - | 8 | × | 1 |
| x | = | - | 8 |