( | 80 | − | 2 | X | ) | ( | 50 | − | 2 | X | ) | = | 5400 |
Left side of the equation = | 80 | ( | 50 | − | 2 | X | ) | − | 2 | X | ( | 50 | − | 2 | X | ) |
= | 80 | × | 50 | − | 80 | × | 2 | X | − | 2 | X | ( | 50 | − | 2 | X | ) |
= | 4000 | − | 160 | X | − | 2 | X | ( | 50 | − | 2 | X | ) |
= | 4000 | − | 160 | X | − | 2 | X | × | 50 | + | 2 | X | × | 2 | X |
= | 4000 | − | 160 | X | − | 100 | X | + | 4 | X | X |
= | 4000 | − | 260 | X | + | 4 | X | X |
4000 | − | 260 | X | + | 4 | X | X | = | 5400 |