| ( | 13 2 | + | 8 | − | x | ) | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 32 | + | 3 2 | = | 18 |
| 方程左边 = | ( | 13 2 | + | 8 | − | x | ) | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 61 2 |
| ( | 13 2 | + | 8 | − | x | ) | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 61 2 | = | 18 |
| 方程左边 = | 13 2 | ( | 2 | x | − | 3 | ) | + | 8 | ( | 2 | x | − | 3 | ) | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 61 2 |
| = | 13 2 | × | 2 | x | − | 13 2 | × | 3 | + | 8 | ( | 2 | x | − | 3 | ) | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 61 2 |
| = | 13 | x | − | 39 2 | + | 8 | ( | 2 | x | − | 3 | ) | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) | − | 61 2 |
| = | 13 | x | − | 50 | + | 8 | ( | 2 | x | − | 3 | ) | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 13 | x | − | 50 | + | 8 | × | 2 | x | − | 8 | × | 3 | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 13 | x | − | 50 | + | 16 | x | − | 24 | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 29 | x | − | 74 | − | x | ( | 2 | x | − | 3 | ) | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 29 | x | − | 74 | − | x | × | 2 | x | + | x | × | 3 | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 32 | x | − | 74 | − | x | × | 2 | x | − | ( | 8 | − | x | ) | ( | 2 | x | − | 7 | ) |
| = | 32 | x | − | 74 | − | x | × | 2 | x | − | 8 | ( | 2 | x | − | 7 | ) | + | x | ( | 2 | x | − | 7 | ) |
| = | 32 | x | − | 74 | − | x | × | 2 | x | − | 8 | × | 2 | x | + | 8 | × | 7 | + | x |
| = | 32 | x | − | 74 | − | x | × | 2 | x | − | 16 | x | + | 56 | + | x | ( | 2 | x | − | 7 | ) |
| = | 16 | x | − | 18 | − | x | × | 2 | x | + | x | ( | 2 | x | − | 7 | ) |
| = | 16 | x | − | 18 | − | x | × | 2 | x | + | x | × | 2 | x | − | x | × | 7 |
| = | 9 | x | − | 18 | − | x | × | 2 | x | + | x | × | 2 | x |
| 9 | x | − | 18 | − | x | × | 2 | x | + | x | × | 2 | x | = | 18 |