| ( | ( | 5000000 | − | 500000 | ) | ÷ | ( | 4000 | − | x | ) | ) | = | ( | ( | 8000000 | ) | ÷ | ( | 4000 | ) | ) |
| ( | 5000000 | − | 500000 | ) | ÷ | ( | 4000 | − | x | ) | = | ( | ( | 8000000 | ) | ÷ | ( | 4000 | ) | ) |
| ( | 5000000 | − | 500000 | ) | ÷ | ( | 4000 | − | x | ) | = | ( | 8000000 | ) | ÷ | ( | 4000 | ) |
| 方程两边同时乘以: | ( | 4000 | − | x | ) | , | ( | 4000 | ) |
| ( | 5000000 | − | 500000 | ) | ( | 4000 | ) | = | ( | 8000000 | ) | ( | 4000 | − | x | ) |
| 5000000 | ( | 4000 | ) | − | 500000 | ( | 4000 | ) | = | ( | 8000000 | ) | ( | 4000 | − | x | ) |
| 5000000 | ( | 4000 | ) | − | 500000 | ( | 4000 | ) | = | 8000000 | ( | 4000 | − | x | ) |
| 5000000 | × | 4000 | − | 500000 | ( | 4000 | ) | = | 8000000 | ( | 4000 | − | x | ) |
| 5000000 | × | 4000 | − | 500000 | ( | 4000 | ) | = | 8000000 | × | 4000 | − | 8000000 | x |