| ( | 3 5 | − | x | ) | ( | 1 2 | − | x | ) | ÷ | ( | 1 5 | + | x | ) | = | 1 8 |
| 方程两边同时乘以: | ( | 1 5 | + | x | ) |
| ( | 3 5 | − | x | ) | ( | 1 2 | − | x | ) | = | 1 8 | ( | 1 5 | + | x | ) |
3 5 | ( | 1 2 | − | x | ) | − | x | ( | 1 2 | − | x | ) | = | 1 8 | ( | 1 5 | + | x | ) |
3 5 | ( | 1 2 | − | x | ) | − | x | ( | 1 2 | − | x | ) | = | 1 8 | × | 1 5 | + | 1 8 | x |
3 5 | ( | 1 2 | − | x | ) | − | x | ( | 1 2 | − | x | ) | = | 1 40 | + | 1 8 | x |
3 5 | × | 1 2 | − | 3 5 | x | − | x | ( | 1 2 | − | x | ) | = | 1 40 | + | 1 8 | x |
3 10 | − | 3 5 | x | − | x | ( | 1 2 | − | x | ) | = | 1 40 | + | 1 8 | x |
3 10 | − | 3 5 | x | − | x | × | 1 2 | + | x | x | = | 1 40 | + | 1 8 | x |
3 10 | − | 11 10 | x | + | x | x | = | 1 40 | + | 1 8 | x |