| ( | x | + | 200 | ) | ÷ | ( | 1 | − | 10 100 | ) | = | ( | x | + | 100 | ) | ÷ | ( | 1 | − | 10 100 | ) |
| 方程两边同时乘以: | ( | 1 | − | 10 100 | ) | , | ( | 1 | − | 10 100 | ) |
| ( | x | + | 200 | ) | ( | 1 | − | 10 100 | ) | = | ( | x | + | 100 | ) | ( | 1 | − | 10 100 | ) |
| x | ( | 1 | − | 10 100 | ) | + | 200 | ( | 1 | − | 10 100 | ) | = | ( | x | + | 100 | ) | ( | 1 | − | 10 100 | ) |
| x | ( | 1 | − | 10 100 | ) | + | 200 | ( | 1 | − | 10 100 | ) | = | x | ( | 1 | − | 10 100 | ) | + | 100 | ( | 1 | − | 10 100 | ) |
| x | × | 1 | − | x | × | 10 100 | + | 200 | ( | 1 | − | 10 100 | ) | = | x | ( | 1 | − | 10 100 | ) | + | 100 | ( | 1 | − | 10 100 | ) |
| x | × | 1 | − | x | × | 10 100 | + | 200 | ( | 1 | − | 10 100 | ) | = | x | × | 1 | − | x | × | 10 100 | + | 100 | ( | 1 | − | 10 100 | ) |
9 10 | x | + | 200 | ( | 1 | − | 10 100 | ) | = | 9 10 | x | + | 100 | ( | 1 | − | 10 100 | ) |
9 10 | x | + | 200 | × | 1 | − | 200 | × | 10 100 | = | 9 10 | x | + | 100 | ( | 1 | − | 10 100 | ) |
9 10 | x | + | 200 | × | 1 | − | 200 | × | 10 100 | = | 9 10 | x | + | 100 | × | 1 | − | 100 | × | 10 100 |
9 10 | x | + | 200 | − | 20 | = | 9 10 | x | + | 100 | − | 10 |
9 10 | x | + | 180 | = | 9 10 | x | + | 90 |
9 10 | x | − | 9 10 | x | = | 90 | − | 180 |
| 0 | x | = | 90 | − | 180 |
| 0 | x | = | - | 90 |