| 33 | ( | 1 20 | − | x | ) | ( | 3 200 | − | x | ) | = | x |
| Left side of the equation = | 33 | × | 1 20 | ( | 3 200 | − | x | ) | − | 33 | x | ( | 3 200 | − | x | ) |
| = | 33 20 | ( | 3 200 | − | x | ) | − | 33 | x | ( | 3 200 | − | x | ) |
| = | 33 20 | × | 3 200 | − | 33 20 | x | − | 33 | x | ( | 3 200 | − | x | ) |
| = | 99 4000 | − | 33 20 | x | − | 33 | x | ( | 3 200 | − | x | ) |
| = | 99 4000 | − | 33 20 | x | − | 33 | x | × | 3 200 | + | 33 | x | x |
| = | 99 4000 | − | 33 20 | x | − | 99 200 | x | + | 33 | x | x |
| = | 99 4000 | − | 429 200 | x | + | 33 | x | x |
99 4000 | − | 429 200 | x | + | 33 | x | x | = | x |