9 10 | x | × | 8 | − | 8 | ( | x | − | 60 | ) | = | ( | x | − | 20 | ) | × | 6 | − | 6 | ( | x | − | 60 | ) |
| 方程左边 = | 36 5 | x | − | 8 | ( | x | − | 60 | ) |
36 5 | x | − | 8 | ( | x | − | 60 | ) | = | ( | x | − | 20 | ) | × | 6 | − | 6 | ( | x | − | 60 | ) |
| 方程左边 = | 36 5 | x | − | 8 | x | + | 8 | × | 60 |
| = | 36 5 | x | − | 8 | x | + | 480 |
| = | - | 4 5 | x | + | 480 |
| - | 4 5 | x | + | 480 | = | ( | x | − | 20 | ) | × | 6 | − | 6 | ( | x | − | 60 | ) |
| 方程右边 = | x | × | 6 | − | 20 | × | 6 | − | 6 | ( | x | − | 60 | ) |
| = | x | × | 6 | − | 120 | − | 6 | ( | x | − | 60 | ) |
| = | 6 | x | − | 120 | − | 6 | x | + | 6 | × | 60 |
| = | 6 | x | − | 120 | − | 6 | x | + | 360 |
| = | 0 | x | + | 240 |
| - | 4 5 | x | + | 480 | = | 0 | x | + | 240 |
| - | 4 5 | x | = | 240 | − | 480 |
| - | 4 5 | x | = | - | 240 |
| 240 | = | 4 5 | x |
4 5 | x | = | 240 |
| x | = | 240 | ÷ | 4 5 |
| = | 240 | × | 5 4 |
| = | 60 | × | 5 |
| x | = | 300 |