77 500 | = | ( | x | − | 87 | ) | ÷ | ( | x | − | 87 | + | 87 | ) |
| 方程两边同时乘以: | ( | x | − | 87 | + | 87 | ) |
77 500 | ( | x | − | 87 | + | 87 | ) | = | ( | x | − | 87 | ) |
77 500 | x | − | 77 500 | × | 87 | + | 77 500 | × | 87 | = | ( | x | − | 87 | ) |
77 500 | x | − | 77 500 | × | 87 | + | 77 500 | × | 87 | = | x | − | 87 |
77 500 | x | − | 6699 500 | + | 6699 500 | = | x | − | 87 |
77 500 | x | − | 0 | = | x | − | 87 |
77 500 | x | − | x | = | - | 87 |
| - | 423 500 | x | = | - | 87 |
| 87 | = | 423 500 | x |
423 500 | x | = | 87 |
| x | = | 87 | ÷ | 423 500 |
| = | 87 | × | 500 423 |
| = | 29 | × | 500 141 |
| x | = | 14500 141 |
| x | = | 102.836879 |