| 27 | + | 2 | x | × | 3 | = | 4 | x | + | 39 |
| 方程左边 = | 27 | + | 6 | x |
| 27 | + | 6 | x | = | 4 | x | + | 39 |
| 6 | x | − | 4 | x | = | 39 | − | 27 |
| 2 | x | = | 39 | − | 27 |
| 2 | x | = | 12 |
| x | = | 12 | ÷ | 2 |
| = | 12 | × | 1 2 |
| = | 6 | × | 1 |
| x | = | 6 |
| ( | x | − | 13 2 | ) | × | 6 5 | = | 18 5 |
| 方程左边 = | x | × | 6 5 | − | 13 2 | × | 6 5 |
| = | x | × | 6 5 | − | 39 5 |
6 5 | x | − | 39 5 | = | 18 5 |
6 5 | x | = | 18 5 | + | 39 5 |
6 5 | x | = | 57 5 |
| x | = | 57 5 | ÷ | 6 5 |
| = | 57 5 | × | 5 6 |
| = | 19 | × | 1 2 |
| x | = | 19 2 |
| x | = | 9.5 |
| ( | 7 | ÷ | 7 | ) | x | + | 2 | x | + | 11 | = | 38 |
| 方程左边 = | 7 | ÷ | 7 | × | x | + | 2 | x | + | 11 |
| = | 1 | x | + | 2 | x | + | 11 |
| = | 3 | x | + | 11 |
| 3 | x | + | 11 | = | 38 |
| 3 | x | = | 38 | − | 11 |
| 3 | x | = | 27 |
| x | = | 27 | ÷ | 3 |
| = | 27 | × | 1 3 |
| = | 9 | × | 1 |
| x | = | 9 |