| 5 | ( | 4 | − | ( | m | ÷ | 2 | ) | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) | = | m | ( | m | − | 4 | ) |
| 方程左边 = | 5 | × | 4 | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 20 | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 20 | × | 8 | + | 20 | ( | 3 | m | ÷ | 10 | ) | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 20 | ( | 3 | m | ÷ | 10 | ) | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 20 | × | 3 | m | ÷ | 10 | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 6 | m | − | 5 | ( | m | ÷ | 2 | ) | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 6 | m | − | 5 | m | ÷ | 2 | × | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 6 | m | − | 5 2 | m | ( | 8 | + | ( | 3 | m | ÷ | 10 | ) | ) |
| = | 160 | + | 6 | m | − | 5 2 | m | × | 8 | − | 5 2 | m | ( | 3 | m | ÷ | 10 | ) |
| = | 160 | + | 6 | m | − | 20 | m | − | 5 2 | m | ( | 3 | m | ÷ | 10 | ) |
| = | 160 | − | 14 | m | − | 5 2 | m | ( | 3 | m | ÷ | 10 | ) |
| = | 160 | − | 14 | m | − | 5 2 | m | × | 3 | m | ÷ | 10 |
| = | 160 | − | 14 | m | − | 3 4 | m | m |
| 160 | − | 14 | m | − | 3 4 | m | m | = | m | ( | m | − | 4 | ) |
| 方程右边 = | m | m | − | m | × | 4 |
| 160 | − | 14 | m | − | 3 4 | m | m | = | m | m | − | 4 | m |