| ( | X | ) | − | ( | X | × | 6 100 | ) | − | ( | X | × | 59 500 | ) | = | 42340 |
| 方程左边 = | X | − | ( | X | × | 6 100 | ) | − | ( | X | × | 59 500 | ) |
| = | X | − | X | × | 6 100 | − | ( | X | × | 59 500 | ) |
| = | 47 50 | X | − | ( | X | × | 59 500 | ) |
| = | 47 50 | X | − | X | × | 59 500 |
| = | 411 500 | X |
411 500 | X | = | 42340 |
| X | = | 42340 | ÷ | 411 500 |
| = | 42340 | × | 500 411 |
| X | = | 21170000 411 |
| X | = | 51508.515815 |