| ( | 40 | − | x | ) | ( | 10 | + | 3 | x | ÷ | 25 | ) | = | 4600 |
| Left side of the equation = | 40 | ( | 10 | + | 3 | x | ÷ | 25 | ) | − | x | ( | 10 | + | 3 | x | ÷ | 25 | ) |
| = | 40 | × | 10 | + | 40 | × | 3 | x | ÷ | 25 | − | x | ( | 10 | + | 3 | x | ÷ | 25 | ) |
| = | 400 | + | 24 5 | x | − | x | ( | 10 | + | 3 | x | ÷ | 25 | ) |
| = | 400 | + | 24 5 | x | − | x | × | 10 | − | x | × | 3 | x | ÷ | 25 |
| = | 400 | + | 24 5 | x | − | x | × | 10 | − | x | × | 3 25 | x |
| = | 400 | − | 26 5 | x | − | x | × | 3 25 | x |
| 400 | − | 26 5 | x | − | x | × | 3 25 | x | = | 4600 |