| ( | 64 | − | y | ÷ | 10 | ) | ( | 200 | + | y | ) | = | 14400 |
| 方程左边 = | 64 | ( | 200 | + | y | ) | − | y | ÷ | 10 | × | ( | 200 | + | y | ) |
| = | 64 | × | 200 | + | 64 | y | − | y | × | 1 10 | ( | 200 | + | y | ) |
| = | 12800 | + | 64 | y | − | y | × | 1 10 | ( | 200 | + | y | ) |
| = | 12800 | + | 64 | y | − | y | × | 1 10 | × | 200 | − | y | × | 1 10 | y |
| = | 12800 | + | 64 | y | − | y | × | 20 | − | y | × | 1 10 | y |
| = | 12800 | + | 44 | y | − | y | × | 1 10 | y |
| 12800 | + | 44 | y | − | y | × | 1 10 | y | = | 14400 |