| 4000 | ÷ | ( | ( | 73 2 | + | x | ÷ | 2 | ) | × | 102 | x | ) | = | 355 |
| 方程两边同时乘以: | ( | ( | 73 2 | + | x | ÷ | 2 | ) | × | 102 | x | ) |
| 4000 | = | 355 | ( | ( | 73 2 | + | x | ÷ | 2 | ) | × | 102 | x | ) |
| 4000 | = | 355 | ( | 73 2 | + | x | ÷ | 2 | ) | × | 102 | x |
| 4000 | = | 36210 | ( | 73 2 | + | x | ÷ | 2 | ) | x |
| 4000 | = | 36210 | × | 73 2 | x | + | 36210 | x | ÷ | 2 | × | x |
| 4000 | = | 1321665 | x | + | 18105 | x | x |