| ( | 3 | + | 1 | ÷ | 5 | ) | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) | = | ( | 4 | X | + | 16 | ) | ( | 48 | ÷ | 15 | ) |
| 方程左边 = | 3 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) | + | 1 | ÷ | 5 | × | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 3 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 3 | × | 5 | ( | X | + | 2 | ) | + | 3 | × | 1 | ÷ | 3 | × | ( | X | + | 2 | ) | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 15 | ( | X | + | 2 | ) | + | 1 | ( | X | + | 2 | ) | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 15 | X | + | 15 | × | 2 | + | 1 | ( | X | + | 2 | ) | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 15 | X | + | 30 | + | 1 | ( | X | + | 2 | ) | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 15 | X | + | 30 | + | 1 | X | + | 1 | × | 2 | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 15 | X | + | 30 | + | 1 | X | + | 2 | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 16 | X | + | 32 | + | 1 5 | ( | 5 | + | 1 | ÷ | 3 | ) | ( | X | + | 2 | ) |
| = | 16 | X | + | 32 | + | 1 5 | × | 5 | ( | X | + | 2 | ) | + | 1 5 | × | 1 | ÷ | 3 | × | ( | X | + | 2 | ) |
| = | 16 | X | + | 32 | + | 1 | ( | X | + | 2 | ) | + | 1 15 | ( | X | + | 2 | ) |
| = | 16 | X | + | 32 | + | 1 | X | + | 1 | × | 2 | + | 1 15 | ( | X | + | 2 | ) |
| = | 16 | X | + | 32 | + | 1 | X | + | 2 | + | 1 15 | ( | X | + | 2 | ) |
| = | 17 | X | + | 34 | + | 1 15 | ( | X | + | 2 | ) |
| = | 17 | X | + | 34 | + | 1 15 | X | + | 1 15 | × | 2 |
| = | 17 | X | + | 34 | + | 1 15 | X | + | 2 15 |
| = | 256 15 | X | + | 512 15 |
256 15 | X | + | 512 15 | = | ( | 4 | X | + | 16 | ) | ( | 48 | ÷ | 15 | ) |
| 方程右边 = | 4 | X | ( | 48 | ÷ | 15 | ) | + | 16 | ( | 48 | ÷ | 15 | ) |
| = | 4 | X | × | 48 | ÷ | 15 | + | 16 | ( | 48 | ÷ | 15 | ) |
| = | 64 5 | X | + | 16 | ( | 48 | ÷ | 15 | ) |
| = | 64 5 | X | + | 16 | × | 48 | ÷ | 15 |
| = | 64 5 | X | + | 256 5 |
256 15 | X | + | 512 15 | = | 64 5 | X | + | 256 5 |
256 15 | X | − | 64 5 | X | = | 256 5 | − | 512 15 |
64 15 | X | = | 256 5 | − | 512 15 |
64 15 | X | = | 256 15 |
| X | = | 256 15 | ÷ | 64 15 |
| = | 256 15 | × | 15 64 |
| = | 4 | × | 1 |
| X | = | 4 |