| 2000 | + | ( | 50 | x | + | 200 | ) | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) | − | 600 | × | 6 | = | 1050 |
| 方程左边 = | 2000 | + | ( | 50 | x | + | 200 | ) | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) | − | 3600 |
| = | - | 1600 | + | ( | 50 | x | + | 200 | ) | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| - | 1600 | + | ( | 50 | x | + | 200 | ) | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) | = | 1050 |
| 方程左边 = | - | 1600 | + | 50 | x | ( | 10 | − | x | ) | + | 200 | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| = | - | 1600 | + | 50 | x | × | 10 | − | 50 | x | x | + | 200 | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| = | - | 1600 | + | 500 | x | − | 50 | x | x | + | 200 | ( | 10 | − | x | ) | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| = | - | 1600 | + | 500 | x | − | 50 | x | x | + | 200 | × | 10 | − | 200 | x | + | 4 | x |
| = | - | 1600 | + | 500 | x | − | 50 | x | x | + | 2000 | − | 200 | x | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| = | 400 | + | 300 | x | − | 50 | x | x | + | 4 | x | ( | 600 | − | 50 | x | + | 200 | ) |
| = | 400 | + | 300 | x | − | 50 | x | x | + | 4 | x | × | 600 | − | 4 | x | × | 50 |
| = | 400 | + | 300 | x | − | 50 | x | x | + | 2400 | x | − | 200 | x | x | + | 800 |
| = | 400 | + | 3500 | x | − | 50 | x | x | − | 200 | x | x |
| 400 | + | 3500 | x | − | 50 | x | x | − | 200 | x | x | = | 1050 |