| 10 | x | = | ( | x | + | 42 | ) | x | ( | 10 | − | 3 | ) |
| Right side of the equation = | x | x | ( | 10 | − | 3 | ) | + | 42 | x | ( | 10 | − | 3 | ) |
| = | x | x | × | 10 | − | x | x | × | 3 | + | 42 | x | ( | 10 | − | 3 | ) |
| = | x | x | × | 10 | − | x | x | × | 3 | + | 42 | x | × | 10 | − | 42 | x | × | 3 |
| = | x | x | × | 10 | − | x | x | × | 3 | + | 420 | x | − | 126 | x |
| = | x | x | × | 10 | − | x | x | × | 3 | + | 294 | x |
| 10 | x | = | x | x | × | 10 | − | x | x | × | 3 | + | 294 | x |