| - | 2 | ( | k | − | 3 | ) | = | 4 | ( | 2 | k | + | 4 | ) |
| 方程左边 = | - | 2 | k | + | 2 | × | 3 |
| = | - | 2 | k | + | 6 |
| - | 2 | k | + | 6 | = | 4 | ( | 2 | k | + | 4 | ) |
| 方程右边 = | 4 | × | 2 | k | + | 4 | × | 4 |
| = | 8 | k | + | 16 |
| - | 2 | k | + | 6 | = | 8 | k | + | 16 |
| - | 2 | k | − | 8 | k | = | 16 | − | 6 |
| - | 10 | k | = | 16 | − | 6 |
| - | 10 | k | = | 10 |
| - | 10 | = | 10 | k |
| 10 | k | = | - | 10 |
| k | = | - | 10 | ÷ | 10 |
| = | - | 10 | × | 1 10 |
| = | - | 1 | × | 1 |
| k | = | - | 1 |