| x | x | + | 36 | = | ( | 8 | − | x | ) | ( | 8 | − | x | ) | + | 20 |
| Right side of the equation = | 8 | ( | 8 | − | x | ) | − | x | ( | 8 | − | x | ) | + | 20 |
| = | 8 | × | 8 | − | 8 | x | − | x | ( | 8 | − | x | ) | + | 20 |
| = | 64 | − | 8 | x | − | x | ( | 8 | − | x | ) | + | 20 |
| = | 84 | − | 8 | x | − | x | ( | 8 | − | x | ) |
| = | 84 | − | 8 | x | − | x | × | 8 | + | x | x |
| = | 84 | − | 16 | x | + | x | x |
| x | x | + | 36 | = | 84 | − | 16 | x | + | x | x |