70 100 | − | 15 100 | − | ( | ( | 1 | + | 10 100 | ) | ÷ | 10 100 | ) | × | 8 100 | x | = | 0 |
| 方程左边 = | 11 20 | − | ( | ( | 1 | + | 10 100 | ) | ÷ | 10 100 | ) | × | 8 100 | x |
11 20 | − | ( | ( | 1 | + | 10 100 | ) | ÷ | 10 100 | ) | × | 8 100 | x | = | 0 |
| 方程左边 = | 11 20 | − | ( | 1 | + | 10 100 | ) | ÷ | 10 100 | × | 8 100 | x |
| = | 11 20 | − | ( | 1 | + | 10 100 | ) | × | 4 5 | x |
| = | 11 20 | − | 1 | × | 4 5 | x | − | 10 100 | × | 4 5 | x |
| = | 11 20 | − | 4 5 | x | − | 2 25 | x |
| = | 11 20 | − | 22 25 | x |
11 20 | − | 22 25 | x | = | 0 |
| - | 22 25 | x | = | 0 | − | 11 20 |
| - | 22 25 | x | = | - | 11 20 |
11 20 | = | 22 25 | x |
22 25 | x | = | 11 20 |
| x | = | 11 20 | ÷ | 22 25 |
| = | 11 20 | × | 25 22 |
| = | 1 4 | × | 5 2 |
| x | = | 5 8 |
| x | = | 0.625 |