| ( | 1 | ÷ | ( | 9 | + | 12 | ) | + | 1 | ÷ | ( | 16 | + | 12 | x | ) | ) | × | 12 | = | x |
| 1 | ÷ | ( | 9 | + | 12 | ) | × | 12 | + | 1 | ÷ | ( | 16 | + | 12 | x | ) | × | 12 | = | x |
| 12 | ÷ | ( | 9 | + | 12 | ) | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | = | x |
| 方程两边同时乘以: | ( | 9 | + | 12 | ) |
| 12 | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | × | ( | 9 | + | 12 | ) | = | x | ( | 9 | + | 12 | ) |
| 12 | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | × | 9 | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | × | 12 | = | x | ( | 9 | + | 12 | ) |
| 12 | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | × | 9 | + | 12 | ÷ | ( | 16 | + | 12 | x | ) | × | 12 | = | x | × | 9 | + | x | × | 12 |
| 12 | + | 108 | ÷ | ( | 16 | + | 12 | x | ) | + | 144 | ÷ | ( | 16 | + | 12 | x | ) | = | x | × | 9 | + | x | × | 12 |
| 12 | + | 108 | ÷ | ( | 16 | + | 12 | x | ) | + | 144 | ÷ | ( | 16 | + | 12 | x | ) | = | 21 | x |
| 方程两边同时乘以: | ( | 16 | + | 12 | x | ) |
| 12 | ( | 16 | + | 12 | x | ) | + | 108 | + | 144 | = | 21 | x | ( | 16 | + | 12 | x | ) |
| 12 | × | 16 | + | 12 | × | 12 | x | + | 108 | + | 144 | = | 21 | x | ( | 16 | + | 12 | x | ) |
| 12 | × | 16 | + | 12 | × | 12 | x | + | 108 | + | 144 | = | 21 | x | × | 16 | + | 21 | x | × | 12 | x |
| 192 | + | 144 | x | + | 108 | + | 144 | = | 336 | x | + | 252 | x | x |
| 444 | + | 144 | x | = | 336 | x | + | 252 | x | x |
| x1=1 |