| 30 | x | × | 4 | − | 240 | x | × | 3 | + | 696 | x | × | 2 | − | 864 | x | + | 386 | = | 0 |
| Left side of the equation = | 120 | x | − | 720 | x | + | 1392 | x | − | 864 | x | + | 386 |
| = | - | 72 | x | + | 386 |
| - | 72 | x | + | 386 | = | 0 |
| - | 72 | x | = | 0 | − | 386 |
| - | 72 | x | = | - | 386 |
| 386 | = | 72 | x |
| 72 | x | = | 386 |
| x | = | 386 | ÷ | 72 |
| = | 386 | × | 1 72 |
| = | 193 | × | 1 36 |
| x | = | 193 36 |
| x | = | 5.361111 |