| 5 | ( | 1 | − | 75 | × | x% | ) | × | 2500 | ( | 1 | + | 5 2 | × | x% | ) | + | 4500 | × | 7 | = | ( | 4500 | × | 7 | + | 2500 | × | 5 | ) | ( | 1 | + | ( | 5 | ÷ | 11 | ) | × | x% | ) |
| 方程左边 = | 12500 | ( | 1 | − | 75 | × | x% | ) | ( | 1 | + | 5 2 | × | x% | ) | + | 31500 |
| 12500 | ( | 1 | − | 75 | × | 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 | × | 75 | × | 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 | + | 625 2 | x | − | 9375 | x | ( | 1 | + | 5 2 | × | x% | ) | + | 31500 |
| = | 44000 | + | 625 2 | x | − | 9375 | x | ( | 1 | + | 5 2 | × | x% | ) |
| = | 44000 | + | 625 2 | x | − | 9375 | x | × | 1 | − | 9375 | x | × | 5 2 | × | x% |
| = | 44000 | + | 625 2 | x | − | 9375 | x | − | 1875 8 | x | x |
| = | 44000 | − | 18125 2 | x | − | 1875 8 | x | x |
| 44000 | − | 18125 2 | x | − | 1875 8 | 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 | + | 315 | ( | 5 | ÷ | 11 | ) | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | × | x% | ) |
| = | 31500 | + | 315 | × | 5 | ÷ | 11 | × | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | × | x% | ) |
| = | 31500 | + | 1575 11 | x | + | 12500 | ( | 1 | + | ( | 5 | ÷ | 11 | ) | × | x% | ) |
| = | 31500 | + | 1575 11 | x | + | 12500 | × | 1 | + | 12500 | ( | 5 | ÷ | 11 | ) | × | x% |
| = | 31500 | + | 1575 11 | x | + | 12500 | + | 125 | ( | 5 | ÷ | 11 | ) | x |
| = | 44000 | + | 1575 11 | x | + | 125 | ( | 5 | ÷ | 11 | ) | x |
| = | 44000 | + | 1575 11 | x | + | 125 | × | 5 | ÷ | 11 | × | x |
| = | 44000 | + | 1575 11 | x | + | 625 11 | x |
| = | 44000 | + | 200 | x |
| 44000 | − | 18125 2 | x | − | 1875 8 | x | x | = | 44000 | + | 200 | x |
| x1=0 |