| 5 | x | + | 14 | = | 140 | − | 4 | x |
| 5 | x | + | 4 | x | = | 140 | − | 14 |
| 9 | x | = | 140 | − | 14 |
| 9 | x | = | 126 |
| x | = | 126 | ÷ | 9 |
| = | 126 | × | 1 9 |
| = | 14 | × | 1 |
| x | = | 14 |
| 3 | ( | x | + | 21 10 | ) | = | 21 2 |
| 方程左边 = | 3 | x | + | 3 | × | 21 10 |
| = | 3 | x | + | 63 10 |
| 3 | x | + | 63 10 | = | 21 2 |
| 3 | x | = | 21 2 | − | 63 10 |
| 3 | x | = | 21 5 |
| x | = | 21 5 | ÷ | 3 |
| = | 21 5 | × | 1 3 |
| = | 7 5 | × | 1 |
| x | = | 7 5 |
| x | = | 1.4 |
| 2 | ( | x | − | 7 10 | ) | = | 24 5 |
| 方程左边 = | 2 | x | − | 2 | × | 7 10 |
| = | 2 | x | − | 7 5 |
| 2 | x | − | 7 5 | = | 24 5 |
| 2 | x | = | 24 5 | + | 7 5 |
| 2 | x | = | 31 5 |
| x | = | 31 5 | ÷ | 2 |
| = | 31 5 | × | 1 2 |
| x | = | 31 10 |
| x | = | 3.1 |
| 4 | x | × | 4 | + | 4 | x | × | 3 | − | 23 | = | 89 |
| 方程左边 = | 16 | x | + | 12 | x | − | 23 |
| = | 28 | x | − | 23 |
| 28 | x | − | 23 | = | 89 |
| 28 | x | = | 89 | + | 23 |
| 28 | x | = | 112 |
| x | = | 112 | ÷ | 28 |
| = | 112 | × | 1 28 |
| = | 4 | × | 1 |
| x | = | 4 |
| 4 | x | + | 19 | = | 69 | − | x |
| 4 | x | + | x | = | 69 | − | 19 |
| 5 | x | = | 69 | − | 19 |
| 5 | x | = | 50 |
| x | = | 50 | ÷ | 5 |
| = | 50 | × | 1 5 |
| = | 10 | × | 1 |
| x | = | 10 |
| 3 | x | + | 2 | x | − | 10 | = | 90 |
| 方程左边 = | 5 | x | − | 10 |
| 5 | x | − | 10 | = | 90 |
| 5 | x | = | 90 | + | 10 |
| 5 | x | = | 100 |
| x | = | 100 | ÷ | 5 |
| = | 100 | × | 1 5 |
| = | 20 | × | 1 |
| x | = | 20 |