7 10 | × | 7 10 | ( | x | − | 69 100 | − | 31 100 | x | ) | = | 21 50 | × | 21 50 | x | x |
| Left side of the equation = | 49 100 | ( | x | − | 69 100 | − | 31 100 | x | ) |
49 100 | ( | x | − | 69 100 | − | 31 100 | x | ) | = | 21 50 | × | 21 50 | x | x |
| Left side of the equation = | 49 100 | x | − | 49 100 | × | 69 100 | − | 49 100 | × | 31 100 | x |
| = | 49 100 | x | − | 3381 10000 | − | 1519 10000 | x |
| = | 3381 10000 | x | − | 3381 10000 |
3381 10000 | x | − | 3381 10000 | = | 21 50 | × | 21 50 | x | x |
| Right side of the equation = | 441 2500 | x | x |
3381 10000 | x | − | 3381 10000 | = | 441 2500 | x | x |