| 5 | ( | 1 | − | 3 4 | x | ) | × | 2500 | ( | 1 | + | 5 2 | x | ) | + | 4500 | × | 7 | = | ( | 4500 | × | 7 | + | 2500 | × | 5 | ) | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| 方程左边 = | 12500 | ( | 1 | − | 3 4 | x | ) | ( | 1 | + | 5 2 | x | ) | + | 31500 |
| 12500 | ( | 1 | − | 3 4 | x | ) | ( | 1 | + | 5 2 | x | ) | + | 31500 | = | ( | 4500 | × | 7 | + | 2500 | × | 5 | ) | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| 方程左边 = | 12500 | × | 1 | ( | 1 | + | 5 2 | x | ) | − | 12500 | × | 3 4 | x | ( | 1 | + | 5 2 | x | ) | + | 31500 |
| = | 12500 | ( | 1 | + | 5 2 | x | ) | − | 9375 | x | ( | 1 | + | 5 2 | x | ) | + | 31500 |
| = | 12500 | × | 1 | + | 12500 | × | 5 2 | x | − | 9375 | x | ( | 1 | + | 5 2 | x | ) | + | 31500 |
| = | 12500 | + | 31250 | x | − | 9375 | x | ( | 1 | + | 5 2 | x | ) | + | 31500 |
| = | 44000 | + | 31250 | x | − | 9375 | x | ( | 1 | + | 5 2 | x | ) |
| = | 44000 | + | 31250 | x | − | 9375 | x | × | 1 | − | 9375 | x | × | 5 2 | x |
| = | 44000 | + | 31250 | x | − | 9375 | x | − | 46875 2 | x | x |
| = | 44000 | + | 21875 | x | − | 46875 2 | x | x |
| 44000 | + | 21875 | x | − | 46875 2 | x | x | = | ( | 4500 | × | 7 | + | 2500 | × | 5 | ) | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| 方程右边 = | 4500 | × | 7 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) | + | 2500 | × | 5 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | × | 1 | + | 31500 | ( | 5 | ÷ | 11 | ) | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | + | 31500 | ( | 5 | ÷ | 11 | ) | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | + | 31500 | × | 5 | ÷ | 11 | × | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | + | 157500 11 | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | x | ) |
| = | 31500 | + | 157500 11 | x | + | 12500 | × | 1 | + | 12500 | ( | 5 | ÷ | 11 | ) | x |
| = | 31500 | + | 157500 11 | x | + | 12500 | + | 12500 | ( | 5 | ÷ | 11 | ) | x |
| = | 44000 | + | 157500 11 | x | + | 12500 | ( | 5 | ÷ | 11 | ) | x |
| = | 44000 | + | 157500 11 | x | + | 12500 | × | 5 | ÷ | 11 | × | x |
| = | 44000 | + | 157500 11 | x | + | 62500 11 | x |
| = | 44000 | + | 20000 | x |
| 44000 | + | 21875 | x | − | 46875 2 | x | x | = | 44000 | + | 20000 | x |
| x2= | 2 25 |