| 200 | ( | 10 | − | 6 | ) | + | ( | 4 | − | x | ) | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) | = | 1250 |
| Left side of the equation = | 200 | × | 10 | − | 200 | × | 6 | + | ( | 4 | − | x | ) | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 2000 | − | 1200 | + | ( | 4 | − | x | ) | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 800 | + | ( | 4 | − | x | ) | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 800 | + | 4 | ( | 200 | + | 50 | x | ) | − | x | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 800 | + | 4 | × | 200 | + | 4 | × | 50 | x | − | x | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 800 | + | 800 | + | 200 | x | − | x | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 1600 | + | 200 | x | − | x | ( | 200 | + | 50 | x | ) | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 1600 | + | 200 | x | − | x | × | 200 | − | x | × | 50 | x | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 1600 | + | 0 | x | − | x | × | 50 | x | + | ( | 4 | − | 6 | ) | ( | 200 | − | 50 | x | ) |
| = | 1600 | + | 0 | x | − | x | × | 50 | x | + | 4 | ( | 200 | − | 50 | x | ) | − | 6 | ( | 200 | − | 50 | x | ) |
| = | 1600 | + | 0 | x | − | x | × | 50 | x | + | 4 | × | 200 | − | 4 | × | 50 | x | − | 6 |
| = | 1600 | + | 0 | x | − | x | × | 50 | x | + | 800 | − | 200 | x | − | 6 | ( | 200 | − | 50 | x | ) |
| = | 2400 | − | 200 | x | − | x | × | 50 | x | − | 6 | ( | 200 | − | 50 | x | ) |
| = | 2400 | − | 200 | x | − | x | × | 50 | x | − | 6 | × | 200 | + | 6 | × | 50 | x |
| = | 2400 | − | 200 | x | − | x | × | 50 | x | − | 1200 | + | 300 | x |
| = | 1200 | + | 100 | x | − | x | × | 50 | x |
| 1200 | + | 100 | x | − | x | × | 50 | x | = | 1250 |