| 200 | + | ( | 200 | − | 2 | x | ) | ( | x | − | 1 | ) | + | 100 | ( | 50 | − | x | ) | = | 6240 |
| Left side of the equation = | 200 | + | 200 | ( | x | − | 1 | ) | − | 2 | x | ( | x | − | 1 | ) | + | 100 | ( | 50 | − | x | ) |
| = | 200 | + | 200 | x | − | 200 | × | 1 | − | 2 | x | ( | x | − | 1 | ) | + | 100 | ( | 50 | − | x | ) |
| = | 200 | + | 200 | x | − | 200 | − | 2 | x | ( | x | − | 1 | ) | + | 100 | ( | 50 | − | x | ) |
| = | 0 | + | 200 | x | − | 2 | x | ( | x | − | 1 | ) | + | 100 | ( | 50 | − | x | ) |
| = | 0 | + | 200 | x | − | 2 | x | x | + | 2 | x | × | 1 | + | 100 | ( | 50 | − | x | ) |
| = | 0 | + | 200 | x | − | 2 | x | x | + | 2 | x | + | 100 | ( | 50 | − | x | ) |
| = | 0 | + | 202 | x | − | 2 | x | x | + | 100 | ( | 50 | − | x | ) |
| = | 0 | + | 202 | x | − | 2 | x | x | + | 100 | × | 50 | − | 100 | x |
| = | 0 | + | 202 | x | − | 2 | x | x | + | 5000 | − | 100 | x |
| = | 5000 | + | 102 | x | − | 2 | x | x |
| 5000 | + | 102 | x | − | 2 | x | x | = | 6240 |