79 400 | = | 1 200 | + | 91 50 | ( | y | − | 1 200 | ) |
| Right side of the equation = | 1 200 | + | 91 50 | y | − | 91 50 | × | 1 200 |
| = | 1 200 | + | 91 50 | y | − | 91 10000 |
| = | - | 41 10000 | + | 91 50 | y |
79 400 | = | - | 41 10000 | + | 91 50 | y |
| - | 91 50 | y | = | - | 41 10000 | − | 79 400 |
| - | 91 50 | y | = | - | 126 625 |
126 625 | = | 91 50 | y |
91 50 | y | = | 126 625 |
| y | = | 126 625 | ÷ | 91 50 |
| = | 126 625 | × | 50 91 |
| = | 18 25 | × | 2 13 |
| y | = | 36 325 |
| y | = | 0.110769 |