| x | + | 80 | + | 1 5 | x | + | ( | 6 5 | x | ) | × | 13 100 | = | 2000 |
| 方程左边 = | 6 5 | x | + | 80 | + | ( | 6 5 | x | ) | × | 13 100 |
6 5 | x | + | 80 | + | ( | 6 5 | x | ) | × | 13 100 | = | 2000 |
| 方程左边 = | 6 5 | x | + | 80 | + | 6 5 | x | × | 13 100 |
| = | 6 5 | x | + | 80 | + | 39 250 | x |
| = | 339 250 | x | + | 80 |
339 250 | x | + | 80 | = | 2000 |
339 250 | x | = | 2000 | − | 80 |
339 250 | x | = | 1920 |
| x | = | 1920 | ÷ | 339 250 |
| = | 1920 | × | 250 339 |
| = | 640 | × | 250 113 |
| x | = | 160000 113 |
| x | = | 1415.929204 |