| ( | 900 | ( | 1 | + | x | ) | − | 360 | ) | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | = | 575 |
| 方程左边 = | 900 | ( | 1 | + | x | ) | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | × | 1 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | × | 1 | + | 900 | ( | 8 | ÷ | 9 | ) | x | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 900 | ( | 8 | ÷ | 9 | ) | x | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 900 | × | 8 | ÷ | 9 | × | x | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 800 | x | + | 900 | x | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 800 | x | + | 900 | x | × | 1 | + | 900 | x | ( | 8 | ÷ | 9 | ) | x | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 800 | x | + | 900 | x | + | 900 | x | ( | 8 | ÷ | 9 | ) | x | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 1700 | x | + | 900 | x | ( | 8 | ÷ | 9 | ) | x | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 1700 | x | + | 900 | x | × | 8 | ÷ | 9 | × | x | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 1700 | x | + | 800 | x | x | − | 360 | ( | 1 | + | ( | 8 | ÷ | 9 | ) | x | ) |
| = | 900 | + | 1700 | x | + | 800 | x | x | − | 360 | × | 1 | − | 360 | ( | 8 | ÷ | 9 | ) | x |
| = | 900 | + | 1700 | x | + | 800 | x | x | − | 360 | − | 360 | ( | 8 | ÷ | 9 | ) | x |
| = | 540 | + | 1700 | x | + | 800 | x | x | − | 360 | ( | 8 | ÷ | 9 | ) | x |
| = | 540 | + | 1700 | x | + | 800 | x | x | − | 360 | × | 8 | ÷ | 9 | × | x |
| = | 540 | + | 1700 | x | + | 800 | x | x | − | 320 | x |
| = | 540 | + | 1380 | x | + | 800 | x | x |
| 540 | + | 1380 | x | + | 800 | x | x | = | 575 |
| x1= | - | 7 4 |
| x2= | 1 40 |