| 3 | ( | x | − | 2 | ) | ( | x | − | 3 | ) | = | 5 | x | − | 7 |
| 方程左边 = | 3 | x | ( | x | − | 3 | ) | − | 3 | × | 2 | ( | x | − | 3 | ) |
| = | 3 | x | ( | x | − | 3 | ) | − | 6 | ( | x | − | 3 | ) |
| = | 3 | x | x | − | 3 | x | × | 3 | − | 6 | ( | x | − | 3 | ) |
| = | 3 | x | x | − | 9 | x | − | 6 | ( | x | − | 3 | ) |
| = | 3 | x | x | − | 9 | x | − | 6 | x | + | 6 | × | 3 |
| = | 3 | x | x | − | 9 | x | − | 6 | x | + | 18 |
| = | 3 | x | x | − | 15 | x | + | 18 |
| 3 | x | x | − | 15 | x | + | 18 | = | 5 | x | − | 7 |
| x1= | 5 3 |
| x2=5 |