| ( | 6 | − | x | ) | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) | = | 3 |
| 方程左边 = | 6 | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 6 | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 6 | × | 9 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 6 | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 54 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 6 | × | 4 | ( | 5 | − | x | ) | − | 6 | x | ( | 5 | − | x | ) | − | 54 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 24 | ( | 5 | − | x | ) | − | 6 | x | ( | 5 | − | x | ) | − | 54 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 24 | × | 5 | − | 24 | x | − | 6 | x | ( | 5 | − | x | ) | − | 54 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 120 | − | 24 | x | − | 6 | x | ( | 5 | − | x | ) | − | 54 | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 66 | − | 24 | x | − | 6 | x | ( | 5 | − | x | ) | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 66 | − | 24 | x | − | 6 | x | × | 5 | + | 6 | x | x | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 66 | − | 24 | x | − | 30 | x | + | 6 | x | x | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 66 | − | 54 | x | + | 6 | x | x | − | x | ( | ( | 4 | − | x | ) | ( | 5 | − | x | ) | − | 9 | ) |
| = | 66 | − | 54 | x | + | 6 | x | x | − | x | ( | 4 | − | x | ) | ( | 5 | − | x | ) | + | x | × | 9 |
| = | 66 | − | 45 | x | + | 6 | x | x | − | x | ( | 4 | − | x | ) | ( | 5 | − | x | ) |
| = | 66 | − | 45 | x | + | 6 | x | x | − | x | × | 4 | ( | 5 | − | x | ) | + | x | x | ( | 5 | − | x | ) |
| = | 66 | − | 45 | x | + | 6 | x | x | − | x | × | 4 | × | 5 | + | x | × | 4 | x |
| = | 66 | − | 45 | x | + | 6 | x | x | − | x | × | 20 | + | x | × | 4 | x | + | x |
| = | 66 | − | 65 | x | + | 6 | x | x | + | x | × | 4 | x | + | x | x | ( | 5 | − | x | ) |
| = | 66 | − | 65 | x | + | 6 | x | x | + | x | × | 4 | x | + | x | x | × | 5 |
| 66 | − | 65 | x | + | 6 | x | x | + | x | × | 4 | x | + | x | x | × | 5 | = | 3 |
| x1=7 |