| 4000 | ÷ | ( | 73 2 | + | x | ÷ | 2 | ) | × | 102 | x | = | 355 |
| 方程两边同时乘以: | ( | 73 2 | + | x | ÷ | 2 | ) |
| 4000 | × | 102 | x | = | 355 | ( | 73 2 | + | x | ÷ | 2 | ) |
| 4000 | × | 102 | x | = | 355 | × | 73 2 | + | 355 | x | ÷ | 2 |
| 408000 | x | = | 25915 2 | + | 355 2 | x |
| 408000 | x | − | 355 2 | x | = | 25915 2 |
815645 2 | x | = | 25915 2 |
| x | = | 25915 2 | ÷ | 815645 2 |
| = | 25915 2 | × | 2 815645 |
| = | 5183 | × | 1 163129 |
| x | = | 5183 163129 |
| x | = | 0.031772 |