| 40 | ÷ | ( | 8 | + | 16 | ( | - | x | + | 9 | ) | ) | + | 6 | = | 5 |
| 方程两边同时乘以: | ( | 8 | + | 16 | ( | - | x | + | 9 | ) | ) |
| 40 | + | 6 | ( | 8 | + | 16 | ( | - | x | + | 9 | ) | ) | = | 5 | ( | 8 | + | 16 | ( | - | x | + | 9 | ) | ) |
| 40 | + | 6 | × | 8 | + | 6 | × | 16 | ( | - | x | + | 9 | ) | = | 5 | ( | 8 | + | 16 | ( | - | x | + | 9 | ) | ) |
| 40 | + | 6 | × | 8 | + | 6 | × | 16 | ( | - | x | + | 9 | ) | = | 5 | × | 8 | + | 5 | × | 16 | ( | - | x | + | 9 | ) |
| 40 | + | 48 | + | 96 | ( | - | x | + | 9 | ) | = | 40 | + | 80 | ( | - | x | + | 9 | ) |
| 88 | + | 96 | ( | - | x | + | 9 | ) | = | 40 | + | 80 | ( | - | x | + | 9 | ) |
| 88 | − | 96 | x | + | 96 | × | 9 | = | 40 | + | 80 | ( | - | x | + | 9 | ) |
| 88 | − | 96 | x | + | 96 | × | 9 | = | 40 | − | 80 | x | + | 80 | × | 9 |
| 88 | − | 96 | x | + | 864 | = | 40 | − | 80 | x | + | 720 |
| 952 | − | 96 | x | = | 760 | − | 80 | x |
| - | 96 | x | + | 80 | x | = | 760 | − | 952 |
| - | 16 | x | = | 760 | − | 952 |
| - | 16 | x | = | - | 192 |
| 192 | = | 16 | x |
| 16 | x | = | 192 |
| x | = | 192 | ÷ | 16 |
| = | 192 | × | 1 16 |
| = | 12 | × | 1 |
| x | = | 12 |