| 3 | ( | 7 5 | m | + | 4 | ) | + | 6 | ( | 8 | − | m | ) | = | 24 5 | m | − | 129 5 |
| Left side of the equation = | 3 | × | 7 5 | m | + | 3 | × | 4 | + | 6 | ( | 8 | − | m | ) |
| = | 21 5 | m | + | 12 | + | 6 | ( | 8 | − | m | ) |
| = | 21 5 | m | + | 12 | + | 6 | × | 8 | − | 6 | m |
| = | 21 5 | m | + | 12 | + | 48 | − | 6 | m |
| = | - | 9 5 | m | + | 60 |
| - | 9 5 | m | + | 60 | = | 24 5 | m | − | 129 5 |
| - | 9 5 | m | − | 24 5 | m | = | - | 129 5 | − | 60 |
| - | 33 5 | m | = | - | 129 5 | − | 60 |
| - | 33 5 | m | = | - | 429 5 |
429 5 | = | 33 5 | m |
33 5 | m | = | 429 5 |
| m | = | 429 5 | ÷ | 33 5 |
| = | 429 5 | × | 5 33 |
| = | 13 | × | 1 |
| m | = | 13 |