| 48 | x | ( | 1450 | + | ( | 3625 | − | 12 | x | ) | ÷ | 12 | ) | = | 145 | × | 145 | × | 25 |
| 方程左边 = | 48 | x | × | 1450 | + | 48 | x | ( | 3625 | − | 12 | x | ) | ÷ | 12 |
| = | 69600 | x | + | 4 | x | ( | 3625 | − | 12 | x | ) |
| = | 69600 | x | + | 4 | x | × | 3625 | − | 4 | x | × | 12 | x |
| = | 69600 | x | + | 14500 | x | − | 48 | x | x |
| = | 84100 | x | − | 48 | x | x |
| 84100 | x | − | 48 | x | x | = | 145 | × | 145 | × | 25 |
| 方程右边 = | 525625 |
| 84100 | x | − | 48 | x | x | = | 525625 |