130 | ( | ( | 60 | + | 3 2 | x | ) | ( | x | + | 40 | ) | − | 2000 | ) | = | 642000 |
Left side of the equation = | 130 | ( | 60 | + | 3 2 | x | ) | ( | x | + | 40 | ) | − | 130 | × | 2000 |
= | 130 | ( | 60 | + | 3 2 | x | ) | ( | x | + | 40 | ) | − | 260000 |
= | 130 | × | 60 | ( | x | + | 40 | ) | + | 130 | × | 3 2 | x | ( | x | + | 40 | ) | − | 260000 |
= | 7800 | ( | x | + | 40 | ) | + | 195 | x | ( | x | + | 40 | ) | − | 260000 |
= | 7800 | x | + | 7800 | × | 40 | + | 195 | x | ( | x | + | 40 | ) | − | 260000 |
= | 7800 | x | + | 312000 | + | 195 | x | ( | x | + | 40 | ) | − | 260000 |
= | 7800 | x | + | 52000 | + | 195 | x | ( | x | + | 40 | ) |
= | 7800 | x | + | 52000 | + | 195 | x | x | + | 195 | x | × | 40 |
= | 7800 | x | + | 52000 | + | 195 | x | x | + | 7800 | x |
= | 15600 | x | + | 52000 | + | 195 | x | x |
15600 | x | + | 52000 | + | 195 | x | x | = | 642000 |