| 77 | x | + | ( | 150 | − | x | ) | × | 47 | = | 150 | × | 55 |
| Left side of the equation = | 77 | x | + | 150 | × | 47 | − | x | × | 47 |
| = | 77 | x | + | 7050 | − | x | × | 47 |
| = | 30 | x | + | 7050 |
| 30 | x | + | 7050 | = | 150 | × | 55 |
| Right side of the equation = | 8250 |
| 30 | x | + | 7050 | = | 8250 |
| 30 | x | = | 8250 | − | 7050 |
| 30 | x | = | 1200 |
| x | = | 1200 | ÷ | 30 |
| = | 1200 | × | 1 30 |
| = | 40 | × | 1 |
| x | = | 40 |