| 40 | ÷ | 3 | + | ( | 40 | ÷ | 3 | ) | x | − | 40 | x | = | 5 |
| 方程左边 = | 40 3 | + | ( | 40 | ÷ | 3 | ) | x | − | 40 | x |
40 3 | + | ( | 40 | ÷ | 3 | ) | x | − | 40 | x | = | 5 |
| 方程左边 = | 40 3 | + | 40 | ÷ | 3 | × | x | − | 40 | x |
| = | 40 3 | + | 40 3 | x | − | 40 | x |
| = | 40 3 | − | 80 3 | x |
40 3 | − | 80 3 | x | = | 5 |
| - | 80 3 | x | = | 5 | − | 40 3 |
| - | 80 3 | x | = | - | 25 3 |
25 3 | = | 80 3 | x |
80 3 | x | = | 25 3 |
| x | = | 25 3 | ÷ | 80 3 |
| = | 25 3 | × | 3 80 |
| = | 5 | × | 1 16 |
| x | = | 5 16 |
| x | = | 0.3125 |