| ( | X | − | 6000 | × | 6 100 | ) | × | 75 100 | ÷ | 3600 | = | 0 |
| 方程左边 = | ( | X | − | 6000 | × | 6 100 | ) | × | 1 4800 |
| ( | X | − | 6000 | × | 6 100 | ) | × | 1 4800 | = | 0 |
| 方程左边 = | X | × | 1 4800 | − | 6000 | × | 6 100 | × | 1 4800 |
| = | X | × | 1 4800 | − | 3 40 |
1 4800 | X | − | 3 40 | = | 0 |
1 4800 | X | = | 0 | + | 3 40 |
1 4800 | X | = | 3 40 |
| X | = | 3 40 | ÷ | 1 4800 |
| = | 3 40 | × | 4800 |
| = | 3 | × | 120 |
| X | = | 360 |