| 100 | x | + | 70 | × | 70 | ( | 6 | − | x | ) | = | 285144 25 |
| 方程左边 = | 100 | x | + | 4900 | ( | 6 | − | x | ) |
| 100 | x | + | 4900 | ( | 6 | − | x | ) | = | 285144 25 |
| 方程左边 = | 100 | x | + | 4900 | × | 6 | − | 4900 | x |
| = | 100 | x | + | 29400 | − | 4900 | x |
| = | - | 4800 | x | + | 29400 |
| - | 4800 | x | + | 29400 | = | 285144 25 |
| - | 4800 | x | = | 285144 25 | − | 29400 |
| - | 4800 | x | = | - | 449856 25 |
449856 25 | = | 4800 | x |
| 4800 | x | = | 449856 25 |
| x | = | 449856 25 | ÷ | 4800 |
| = | 449856 25 | × | 1 4800 |
| = | 2343 25 | × | 1 25 |
| x | = | 2343 625 |
| x | = | 3.7488 |