| m | m | + | ( | 10 | − | m | ) | ( | 10 | − | m | ) | = | ( | 8 | − | m | ) | ( | 8 | − | m | ) |
| 方程左边 = | m | m | + | 10 | ( | 10 | − | m | ) | − | m | ( | 10 | − | m | ) |
| = | m | m | + | 10 | × | 10 | − | 10 | m | − | m | ( | 10 | − | m | ) |
| = | m | m | + | 100 | − | 10 | m | − | m | ( | 10 | − | m | ) |
| = | m | m | + | 100 | − | 10 | m | − | m | × | 10 | + | m | m |
| = | m | m | + | 100 | − | 20 | m | + | m | m |
| m | m | + | 100 | − | 20 | m | + | m | m | = | ( | 8 | − | m | ) | ( | 8 | − | m | ) |
| 方程右边 = | 8 | ( | 8 | − | m | ) | − | m | ( | 8 | − | m | ) |
| = | 8 | × | 8 | − | 8 | m | − | m | ( | 8 | − | m | ) |
| = | 64 | − | 8 | m | − | m | ( | 8 | − | m | ) |
| = | 64 | − | 8 | m | − | m | × | 8 | + | m | m |
| = | 64 | − | 16 | m | + | m | m |
| m | m | + | 100 | − | 20 | m | + | m | m | = | 64 | − | 16 | m | + | m | m |