| ( | 159 200 | + | 157 100 | x | ) | ( | x | − | 127 250 | ) | = | 1680 |
| 方程左边 = | 159 200 | ( | x | − | 127 250 | ) | + | 157 100 | x | ( | x | − | 127 250 | ) |
| = | 159 200 | x | − | 159 200 | × | 127 250 | + | 157 100 | x | ( | x | − | 127 250 | ) |
| = | 159 200 | x | − | 20193 50000 | + | 157 100 | x | ( | x | − | 127 250 | ) |
| = | 159 200 | x | − | 20193 50000 | + | 157 100 | x | x | − | 157 100 | x | × | 127 250 |
| = | 159 200 | x | − | 20193 50000 | + | 157 100 | x | x | − | 19939 25000 | x |
| = | - | 8 3125 | x | − | 20193 50000 | + | 157 100 | x | x |
| - | 8 3125 | x | − | 20193 50000 | + | 157 100 | x | x | = | 1680 |