| ( | 17 | − | x | ) | ( | 20 | + | 5 | x | ) | = | ( | 16 | + | x | ) | ( | 16 | + | x | ) |
| Left side of the equation = | 17 | ( | 20 | + | 5 | x | ) | − | x | ( | 20 | + | 5 | x | ) |
| = | 17 | × | 20 | + | 17 | × | 5 | x | − | x | ( | 20 | + | 5 | x | ) |
| = | 340 | + | 85 | x | − | x | ( | 20 | + | 5 | x | ) |
| = | 340 | + | 85 | x | − | x | × | 20 | − | x | × | 5 | x |
| = | 340 | + | 65 | x | − | x | × | 5 | x |
| 340 | + | 65 | x | − | x | × | 5 | x | = | ( | 16 | + | x | ) | ( | 16 | + | x | ) |
| Right side of the equation = | 16 | ( | 16 | + | x | ) | + | x | ( | 16 | + | x | ) |
| = | 16 | × | 16 | + | 16 | x | + | x | ( | 16 | + | x | ) |
| = | 256 | + | 16 | x | + | x | ( | 16 | + | x | ) |
| = | 256 | + | 16 | x | + | x | × | 16 | + | x | x |
| = | 256 | + | 32 | x | + | x | x |
| 340 | + | 65 | x | − | x | × | 5 | x | = | 256 | + | 32 | x | + | x | x |