| ( | 80 | − | 2 | x | ) | ( | 12 | + | 2 | x | ) | − | 16 | = | 1156 | + | 640 |
| Left side of the equation = | 80 | ( | 12 | + | 2 | x | ) | − | 2 | x | ( | 12 | + | 2 | x | ) | − | 16 |
| = | 80 | × | 12 | + | 80 | × | 2 | x | − | 2 | x | ( | 12 | + | 2 | x | ) | − | 16 |
| = | 960 | + | 160 | x | − | 2 | x | ( | 12 | + | 2 | x | ) | − | 16 |
| = | 944 | + | 160 | x | − | 2 | x | ( | 12 | + | 2 | x | ) |
| = | 944 | + | 160 | x | − | 2 | x | × | 12 | − | 2 | x | × | 2 | x |
| = | 944 | + | 160 | x | − | 24 | x | − | 4 | x | x |
| = | 944 | + | 136 | x | − | 4 | x | x |
| 944 | + | 136 | x | − | 4 | x | x | = | 1156 | + | 640 |
| Right side of the equation = | 1796 |
| 944 | + | 136 | x | − | 4 | x | x | = | 1796 |