| 2000 | ( | 1 | + | 2 | a | ) | × | 30 | ( | 1 | − | a | ) | + | 1000 | ( | 1 | − | a | ) | × | 45 | = | 2000 | × | 30 | + | 1000 | × | 45 |
| Left side of the equation = | 60000 | ( | 1 | + | 2 | a | ) | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) |
| 60000 | ( | 1 | + | 2 | a | ) | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) | = | 2000 | × | 30 | + | 1000 | × | 45 |
| Left side of the equation = | 60000 | × | 1 | ( | 1 | − | a | ) | + | 60000 | × | 2 | a | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | ( | 1 | − | a | ) | + | 120000 | a | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | × | 1 | − | 60000 | a | + | 120000 | a | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | − | 60000 | a | + | 120000 | a | ( | 1 | − | a | ) | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | − | 60000 | a | + | 120000 | a | × | 1 | − | 120000 | a | a | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | − | 60000 | a | + | 120000 | a | − | 120000 | a | a | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | + | 60000 | a | − | 120000 | a | a | + | 45000 | ( | 1 | − | a | ) |
| = | 60000 | + | 60000 | a | − | 120000 | a | a | + | 45000 | × | 1 | − | 45000 | a |
| = | 60000 | + | 60000 | a | − | 120000 | a | a | + | 45000 | − | 45000 | a |
| = | 105000 | + | 15000 | a | − | 120000 | a | a |
| 105000 | + | 15000 | a | − | 120000 | a | a | = | 2000 | × | 30 | + | 1000 | × | 45 |
| Right side of the equation = | 60000 | + | 45000 |
| = | 105000 |
| 105000 | + | 15000 | a | − | 120000 | a | a | = | 105000 |
| a2= | 1 8 |