| 19 | ( | 72 | ÷ | 9 | ÷ | x | ) | + | ( | x | ÷ | 2 | ) | + | ( | x | ÷ | 4 | ) | = | 10 | x | − | 1 | + | ( | x | ÷ | 10 | ) | − | x | + | 28 5 |
| 19 | × | 72 | ÷ | 9 | ÷ | x | + | ( | x | ÷ | 2 | ) | + | ( | x | ÷ | 4 | ) | = | 10 | x | − | 1 | + | ( | x | ÷ | 10 | ) | − | x | + | 28 5 |
| 19 | × | 72 | ÷ | 9 | ÷ | x | + | ( | x | ÷ | 2 | ) | + | ( | x | ÷ | 4 | ) | = | 10 | x | − | 1 | + | x | ÷ | 10 | − | x | + | 28 5 |
| 152 | ÷ | x | + | ( | x | ÷ | 2 | ) | + | ( | x | ÷ | 4 | ) | = | 10 | x | − | 1 | + | x | × | 1 10 | − | x | + | 28 5 |
| 152 | ÷ | x | + | ( | x | ÷ | 2 | ) | + | ( | x | ÷ | 4 | ) | = | 91 10 | x | + | 23 5 |
| Multiply both sides of the equation by: | x |
| 152 | + | ( | x | ÷ | 2 | ) | x | + | ( | x | ÷ | 4 | ) | x | = | 91 10 | x | x | + | 23 5 | x |
| 152 | + | x | ÷ | 2 | × | x | + | ( | x | ÷ | 4 | ) | x | = | 91 10 | x | x | + | 23 5 | x |
| 152 | + | x | × | 1 2 | x | + | x | ÷ | 4 | × | x | = | 91 10 | x | x | + | 23 5 | x |
| x1=4 |