| ( | 21 | x | − | 7 | ) | ( | 1 | + | 29 25 | x | ) | = | 54 25 | x |
| Left side of the equation = | 21 | x | ( | 1 | + | 29 25 | x | ) | − | 7 | ( | 1 | + | 29 25 | x | ) |
| = | 21 | x | × | 1 | + | 21 | x | × | 29 25 | x | − | 7 | ( | 1 | + | 29 25 | x | ) |
| = | 21 | x | + | 609 25 | x | x | − | 7 | ( | 1 | + | 29 25 | x | ) |
| = | 21 | x | + | 609 25 | x | x | − | 7 | × | 1 | − | 7 | × | 29 25 | x |
| = | 21 | x | + | 609 25 | x | x | − | 7 | − | 203 25 | x |
| = | 322 25 | x | + | 609 25 | x | x | − | 7 |
322 25 | x | + | 609 25 | x | x | − | 7 | = | 54 25 | x |