| ( | y | − | 2500 | ) | ( | 240 | − | 2 25 | y | ) | = | 5000 |
| Left side of the equation = | y | ( | 240 | − | 2 25 | y | ) | − | 2500 | ( | 240 | − | 2 25 | y | ) |
| = | y | × | 240 | − | y | × | 2 25 | y | − | 2500 | ( | 240 | − | 2 25 | y | ) |
| = | 240 | y | − | y | × | 2 25 | y | − | 2500 | × | 240 | + | 2500 | × | 2 25 | y |
| = | 240 | y | − | y | × | 2 25 | y | − | 600000 | + | 200 | y |
| = | 440 | y | − | y | × | 2 25 | y | − | 600000 |
| 440 | y | − | y | × | 2 25 | y | − | 600000 | = | 5000 |