| ( | 50 | − | 1 | ÷ | 10 | × | x | ) | ( | 80 | + | x | − | 20 | ) | = | 10880 |
| 方程左边 = | 50 | ( | 80 | + | x | − | 20 | ) | − | 1 | ÷ | 10 | × | x | ( | 80 | + | x | − | 20 | ) |
| = | 50 | ( | 80 | + | x | − | 20 | ) | − | 1 10 | x | ( | 80 | + | x | − | 20 | ) |
| = | 50 | × | 80 | + | 50 | x | − | 50 | × | 20 | − | 1 10 | x | ( | 80 | + | x | − | 20 | ) |
| = | 4000 | + | 50 | x | − | 1000 | − | 1 10 | x | ( | 80 | + | x | − | 20 | ) |
| = | 3000 | + | 50 | x | − | 1 10 | x | ( | 80 | + | x | − | 20 | ) |
| = | 3000 | + | 50 | x | − | 1 10 | x | × | 80 | − | 1 10 | x | x | + | 1 10 | x | × | 20 |
| = | 3000 | + | 50 | x | − | 8 | x | − | 1 10 | x | x | + | 2 | x |
| = | 3000 | + | 44 | x | − | 1 10 | x | x |
| 3000 | + | 44 | x | − | 1 10 | x | x | = | 10880 |