| ( | 10 | + | 1 2 | x | ) | ( | 1000 | − | 3 | x | ) | − | 10 | × | 1000 | − | 110 | x | = | 12000 |
| Left side of the equation = | ( | 10 | + | 1 2 | x | ) | ( | 1000 | − | 3 | x | ) | − | 10000 | − | 110 | x |
| ( | 10 | + | 1 2 | x | ) | ( | 1000 | − | 3 | x | ) | − | 10000 | − | 110 | x | = | 12000 |
| Left side of the equation = | 10 | ( | 1000 | − | 3 | x | ) | + | 1 2 | x | ( | 1000 | − | 3 | x | ) | − | 10000 | − | 110 | x |
| = | 10 | × | 1000 | − | 10 | × | 3 | x | + | 1 2 | x | ( | 1000 | − | 3 | x | ) | − | 10000 | − | 110 | x |
| = | 10000 | − | 30 | x | + | 1 2 | x | ( | 1000 | − | 3 | x | ) | − | 10000 | − | 110 | x |
| = | 0 | − | 140 | x | + | 1 2 | x | ( | 1000 | − | 3 | x | ) |
| = | 0 | − | 140 | x | + | 1 2 | x | × | 1000 | − | 1 2 | x | × | 3 | x |
| = | 0 | − | 140 | x | + | 500 | x | − | 3 2 | x | x |
| = | 0 | + | 360 | x | − | 3 2 | x | x |
| 0 | + | 360 | x | − | 3 2 | x | x | = | 12000 |