51 40 | = | ( | 1 5 | − | x | ) | ÷ | ( | 3 10 | − | x | ) |
| 方程两边同时乘以: | ( | 3 10 | − | x | ) |
51 40 | ( | 3 10 | − | x | ) | = | ( | 1 5 | − | x | ) |
51 40 | × | 3 10 | − | 51 40 | x | = | ( | 1 5 | − | x | ) |
51 40 | × | 3 10 | − | 51 40 | x | = | 1 5 | − | x |
153 400 | − | 51 40 | x | = | 1 5 | − | x |
| - | 51 40 | x | + | x | = | 1 5 | − | 153 400 |
| - | 11 40 | x | = | 1 5 | − | 153 400 |
| - | 11 40 | x | = | - | 73 400 |
73 400 | = | 11 40 | x |
11 40 | x | = | 73 400 |
| x | = | 73 400 | ÷ | 11 40 |
| = | 73 400 | × | 40 11 |
| = | 73 10 | × | 1 11 |
| x | = | 73 110 |
| x | = | 0.663636 |