| ( | 3 | − | 2 | x | ) | ( | 1 | + | x | ) | × | 1100 | = | 3388 |
| 方程左边 = | 3 | ( | 1 | + | x | ) | × | 1100 | − | 2 | x | ( | 1 | + | x | ) | × | 1100 |
| = | 3300 | ( | 1 | + | x | ) | − | 2200 | x | ( | 1 | + | x | ) |
| = | 3300 | × | 1 | + | 3300 | x | − | 2200 | x | ( | 1 | + | x | ) |
| = | 3300 | + | 3300 | x | − | 2200 | x | ( | 1 | + | x | ) |
| = | 3300 | + | 3300 | x | − | 2200 | x | × | 1 | − | 2200 | x | x |
| = | 3300 | + | 3300 | x | − | 2200 | x | − | 2200 | x | x |
| = | 3300 | + | 1100 | x | − | 2200 | x | x |
| 3300 | + | 1100 | x | − | 2200 | x | x | = | 3388 |
| x1= | 1 10 |
| x2= | 2 5 |