| ( | 190 | + | 210 | ) | ÷ | x | − | ( | 190 | + | 210 | ) | ÷ | 5 4 | × | x | = | 1 |
| 方程两边同时乘以: | x |
| ( | 190 | + | 210 | ) | − | ( | 190 | + | 210 | ) | ÷ | 5 4 | × | x | x | = | 1 | x |
| 190 | + | 210 | − | ( | 190 | + | 210 | ) | ÷ | 5 4 | × | x | x | = | 1 | x |
| 400 | − | ( | 190 | + | 210 | ) | × | 4 5 | x | x | = | 1 | x |
| 400 | − | 190 | × | 4 5 | x | x | − | 210 | × | 4 5 | x | x | = | 1 | x |
| 400 | − | 152 | x | x | − | 168 | x | x | = | 1 | x |