| 100 | × | 8 5 | x | + | 80 | × | 7 5 | ( | x | + | 5 | ) | = | 1080 |
| Left side of the equation = | 160 | x | + | 112 | ( | x | + | 5 | ) |
| 160 | x | + | 112 | ( | x | + | 5 | ) | = | 1080 |
| Left side of the equation = | 160 | x | + | 112 | x | + | 112 | × | 5 |
| = | 160 | x | + | 112 | x | + | 560 |
| = | 272 | x | + | 560 |
| 272 | x | + | 560 | = | 1080 |
| 272 | x | = | 1080 | − | 560 |
| 272 | x | = | 520 |
| x | = | 520 | ÷ | 272 |
| = | 520 | × | 1 272 |
| = | 65 | × | 1 34 |
| x | = | 65 34 |
| x | = | 1.911765 |