| ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | + | 10 | ÷ | 1 | ) | x | = | 1 | − | ( | 6 | − | x | ) | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| Left side of the equation = | 15 | ÷ | 1 | × | x | + | 20 | ÷ | 1 | × | x | + | 10 | ÷ | 1 | × | x |
| = | 15 | x | + | 20 | x | + | 10 | x |
| = | 45 | x |
| 45 | x | = | 1 | − | ( | 6 | − | x | ) | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| Right side of the equation = | 1 | − | 6 | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) | + | x | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| = | 1 | − | 6 | × | 15 | ÷ | 1 | − | 6 | × | 20 | ÷ | 1 | + | x | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| = | 1 | − | 90 | − | 120 | + | x | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| = | - | 209 | + | x | ( | 15 | ÷ | 1 | + | 20 | ÷ | 1 | ) |
| = | - | 209 | + | x | × | 15 | ÷ | 1 | + | x | × | 20 | ÷ | 1 |
| = | - | 209 | + | x | × | 15 | + | x | × | 20 |
| = | - | 209 | + | 35 | x |
| 45 | x | = | - | 209 | + | 35 | x |
| 45 | x | − | 35 | x | = | - | 209 |
| 10 | x | = | - | 209 |
| x | = | - | 209 | ÷ | 10 |
| = | - | 209 | × | 1 10 |
| x | = | - | 209 10 |
| x | = | - 20.9 |