| 130 | = | 10 | x | + | 120 | ÷ | ( | 1 | + | x | ) | × | ( | 1 | + | x | ) |
| 方程两边同时乘以: | ( | 1 | + | x | ) |
| 130 | ( | 1 | + | x | ) | = | 10 | x | ( | 1 | + | x | ) | + | 120 | ( | 1 | + | x | ) |
| 130 | × | 1 | + | 130 | x | = | 10 | x | ( | 1 | + | x | ) | + | 120 | ( | 1 | + | x | ) |
| 130 | × | 1 | + | 130 | x | = | 10 | x | × | 1 | + | 10 | x | x | + | 120 | ( | 1 | + | x | ) |
| 130 | + | 130 | x | = | 10 | x | + | 10 | x | x | + | 120 | ( | 1 | + | x | ) |
| 130 | + | 130 | x | = | 10 | x | + | 10 | x | x | + | 120 | × | 1 | + | 120 | x |
| 130 | + | 130 | x | = | 10 | x | + | 10 | x | x | + | 120 | + | 120 | x |
| 130 | + | 130 | x | = | 130 | x | + | 10 | x | x | + | 120 |