| ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | ÷ | ( | x | − | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | ) | = | 3 | ÷ | 7 |
| 方程两边同时乘以: | ( | x | − | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | ) |
| ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | = | 3 | ÷ | 7 | × | ( | x | − | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | ) |
| 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | = | 3 | ÷ | 7 | × | ( | x | − | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) | ) |
| 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | = | 3 | ÷ | 7 | × | x | − | 3 | ÷ | 7 | × | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) |
2 15 | x | + | 2 15 | x | + | 6 | = | 3 7 | x | − | 3 7 | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) |
4 15 | x | + | 6 | = | 3 7 | x | − | 3 7 | ( | 2 | ÷ | 15 | × | x | + | 2 | ÷ | 15 | × | x | + | 6 | ) |
4 15 | x | + | 6 | = | 3 7 | x | − | 3 7 | × | 2 | ÷ | 15 | × | x | − | 3 7 | × | 2 | ÷ | 15 | × | x | − | 3 7 | × | 6 |
4 15 | x | + | 6 | = | 3 7 | x | − | 2 35 | x | − | 2 35 | x | − | 18 7 |
4 15 | x | + | 6 | = | 11 35 | x | − | 18 7 |
4 15 | x | − | 11 35 | x | = | - | 18 7 | − | 6 |
| - | 1 21 | x | = | - | 18 7 | − | 6 |
| - | 1 21 | x | = | - | 60 7 |
60 7 | = | 1 21 | x |
1 21 | x | = | 60 7 |
| x | = | 60 7 | ÷ | 1 21 |
| = | 60 7 | × | 21 |
| = | 60 | × | 3 |
| x | = | 180 |