12 5 | x | − | 12 5 | × | 1 2 | = | 6 |
| 方程左边 = | 12 5 | x | − | 6 5 |
12 5 | x | − | 6 5 | = | 6 |
12 5 | x | = | 6 | + | 6 5 |
12 5 | x | = | 36 5 |
| x | = | 36 5 | ÷ | 12 5 |
| = | 36 5 | × | 5 12 |
| = | 3 | × | 1 |
| x | = | 3 |
| 2 | ÷ | 5 | × | x | + | 1 5 | x | = | 18 5 |
| 方程左边 = | 2 5 | x | + | 1 5 | x |
| = | 3 5 | x |
3 5 | x | = | 18 5 |
| x | = | 18 5 | ÷ | 3 5 |
| = | 18 5 | × | 5 3 |
| = | 6 | × | 1 |
| x | = | 6 |
| x | ÷ | ( | 5 | ÷ | 4 | ) | = | 9 | ÷ | 2 | ÷ | ( | 15 | ÷ | 8 | ) |
| 方程两边同时乘以: | ( | 5 | ÷ | 4 | ) | , | ( | 15 | ÷ | 8 | ) |
| x | ( | 15 | ÷ | 8 | ) | = | 9 | ÷ | 2 | × | ( | 5 | ÷ | 4 | ) |
| x | × | 15 | ÷ | 8 | = | 9 | ÷ | 2 | × | ( | 5 | ÷ | 4 | ) |
| x | × | 15 | ÷ | 8 | = | 9 | ÷ | 2 | × | 5 | ÷ | 4 |
| x | × | 15 8 | = | 45 8 |
| x | = | 45 8 | ÷ | 15 8 |
| = | 45 8 | × | 8 15 |
| = | 3 | × | 1 |
| x | = | 3 |