| ( | 4 | t | ) | ÷ | ( | 18 | − | 9 | t | ) | = | ( | 12 | − | 4 | t | ) | ÷ | ( | 34 | − | 3 | t | ) |
| 方程两边同时乘以: | ( | 18 | − | 9 | t | ) | , | ( | 34 | − | 3 | t | ) |
| ( | 4 | t | ) | ( | 34 | − | 3 | t | ) | = | ( | 12 | − | 4 | t | ) | ( | 18 | − | 9 | t | ) |
| 4 | t | ( | 34 | − | 3 | t | ) | = | ( | 12 | − | 4 | t | ) | ( | 18 | − | 9 | t | ) |
| 4 | t | ( | 34 | − | 3 | t | ) | = | 12 | ( | 18 | − | 9 | t | ) | − | 4 | t | ( | 18 | − | 9 | t | ) |
| 4 | t | × | 34 | − | 4 | t | × | 3 | t | = | 12 | ( | 18 | − | 9 | t | ) | − | 4 | t | ( | 18 | − | 9 | t | ) |
| 4 | t | × | 34 | − | 4 | t | × | 3 | t | = | 12 | × | 18 | − | 12 | × | 9 | t | − | 4 | t | ( | 18 | − | 9 | t | ) |
| 136 | t | − | 12 | t | t | = | 216 | − | 108 | t | − | 4 | t | ( | 18 | − | 9 | t | ) |
| 136 | t | − | 12 | t | t | = | 216 | − | 108 | t | − | 4 | t | × | 18 | + | 4 | t | × | 9 | t |
| 136 | t | − | 12 | t | t | = | 216 | − | 108 | t | − | 72 | t | + | 36 | t | t |
| 136 | t | − | 12 | t | t | = | 216 | − | 180 | t | + | 36 | t | t |