| ( | 500 | − | 360 | ) | ÷ | ( | 209 10 | − | X | ) | = | ( | 200 | − | 260 | ) | ÷ | ( | 9 | − | X | ) |
| Multiply both sides of the equation by: | ( | 209 10 | − | X | ) | , | ( | 9 | − | X | ) |
| ( | 500 | − | 360 | ) | ( | 9 | − | X | ) | = | ( | 200 | − | 260 | ) | ( | 209 10 | − | X | ) |
| 500 | ( | 9 | − | X | ) | − | 360 | ( | 9 | − | X | ) | = | ( | 200 | − | 260 | ) | ( | 209 10 | − | X | ) |
| 500 | ( | 9 | − | X | ) | − | 360 | ( | 9 | − | X | ) | = | 200 | ( | 209 10 | − | X | ) | − | 260 | ( | 209 10 | − | X | ) |
| 500 | × | 9 | − | 500 | X | − | 360 | ( | 9 | − | X | ) | = | 200 | ( | 209 10 | − | X | ) | − | 260 | ( | 209 10 | − | X | ) |
| 500 | × | 9 | − | 500 | X | − | 360 | ( | 9 | − | X | ) | = | 200 | × | 209 10 | − | 200 | X | − | 260 | ( | 209 10 | − | X | ) |
| 4500 | − | 500 | X | − | 360 | ( | 9 | − | X | ) | = | 4180 | − | 200 | X | − | 260 | ( | 209 10 | − | X | ) |
| 4500 | − | 500 | X | − | 360 | × | 9 | + | 360 | X | = | 4180 | − | 200 | X | − | 260 | ( | 209 10 | − | X | ) |
| 4500 | − | 500 | X | − | 360 | × | 9 | + | 360 | X | = | 4180 | − | 200 | X | − | 260 | × | 209 10 | + | 260 | X |
| 4500 | − | 500 | X | − | 3240 | + | 360 | X | = | 4180 | − | 200 | X | − | 5434 | + | 260 | X |
| 1260 | − | 140 | X | = | - | 1254 | + | 60 | X |
| - | 140 | X | − | 60 | X | = | - | 1254 | − | 1260 |
| - | 200 | X | = | - | 1254 | − | 1260 |
| - | 200 | X | = | - | 2514 |
| 2514 | = | 200 | X |
| 200 | X | = | 2514 |
| X | = | 2514 | ÷ | 200 |
| = | 2514 | × | 1 200 |
| = | 1257 | × | 1 100 |
| X | = | 1257 100 |
| X | = | 12.57 |