| ( | 666000 | − | 231 500 | x | ) | = | 2783 100000 | × | 99 20 | x |
| 方程左边 = | 666000 | − | 231 500 | x |
| 666000 | − | 231 500 | x | = | 2783 100000 | × | 99 20 | x |
| 方程右边 = | 275517 2000000 | x |
| 666000 | − | 231 500 | x | = | 275517 2000000 | x |
| - | 231 500 | x | − | 275517 2000000 | x | = | - | 666000 |
| - | 1199517 2000000 | x | = | - | 666000 |
| 666000 | = | 1199517 2000000 | x |
1199517 2000000 | x | = | 666000 |
| x | = | 666000 | ÷ | 1199517 2000000 |
| = | 666000 | × | 2000000 1199517 |
| = | 222000 | × | 2000000 399839 |
| x | = | 444000000000 399839 |