| ( | x | + | 10 | × | 2 | ) | × | 9 10 | − | ( | 4 5 | + | 8 | × | 2 | ) | = | 3 |
| 方程左边 = | x | × | 9 10 | + | 10 | × | 2 | × | 9 10 | − | ( | 4 5 | + | 8 | × | 2 | ) |
| = | x | × | 9 10 | + | 18 | − | ( | 4 5 | + | 8 | × | 2 | ) |
| = | 9 10 | x | + | 18 | − | 4 5 | − | 8 | × | 2 |
| = | 9 10 | x | + | 18 | − | 4 5 | − | 16 |
| = | 9 10 | x | + | 6 5 |
9 10 | x | + | 6 5 | = | 3 |
9 10 | x | = | 3 | − | 6 5 |
9 10 | x | = | 9 5 |
| x | = | 9 5 | ÷ | 9 10 |
| = | 9 5 | × | 10 9 |
| = | 1 | × | 2 |
| x | = | 2 |