3 200 | × | 3 200 | = | 3 400 | ( | 13 10 | + | 3 200 | x | ) | ( | 13 10 | + | 3 200 | x | ) |
| 方程左边 = | 9 40000 |
9 40000 | = | 3 400 | ( | 13 10 | + | 3 200 | x | ) | ( | 13 10 | + | 3 200 | x | ) |
| 方程右边 = | 3 400 | × | 13 10 | ( | 13 10 | + | 3 200 | x | ) | + | 3 400 | × | 3 200 | x | ( | 13 10 | + | 3 200 | x | ) |
| = | 39 4000 | ( | 13 10 | + | 3 200 | x | ) | + | 9 80000 | x | ( | 13 10 | + | 3 200 | x | ) |
| = | 39 4000 | × | 13 10 | + | 39 4000 | × | 3 200 | x | + | 9 80000 | x | ( | 13 10 | + | 3 200 | x | ) |
| = | 507 40000 | + | 117 800000 | x | + | 9 80000 | x | ( | 13 10 | + | 3 200 | x | ) |
| = | 507 40000 | + | 117 800000 | x | + | 9 80000 | x | × | 13 10 | + | 9 80000 | x | × | 3 200 | x |
| = | 507 40000 | + | 117 800000 | x | + | 117 800000 | x | + | 27 16000000 | x | x |
| = | 507 40000 | + | 117 400000 | x | + | 27 16000000 | x | x |
9 40000 | = | 507 40000 | + | 117 400000 | x | + | 27 16000000 | x | x |
| x1= | - | 12276709 125000 |