| 2100 | ( | 1 | + | x | ) | + | 2100 | ( | 1 | + | x | ) | ( | 1 | + | 2 | x | ) | × | 11 | + | 700 | ( | 1 | + | 2 | x | ) | × | 12 | = | 15 8 | × | 21700 |
| Left side of the equation = | 2100 | ( | 1 | + | x | ) | + | 23100 | ( | 1 | + | x | ) | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| 2100 | ( | 1 | + | x | ) | + | 23100 | ( | 1 | + | x | ) | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) | = | 15 8 | × | 21700 |
| Left side of the equation = | 2100 | × | 1 | + | 2100 | x | + | 23100 | ( | 1 | + | x | ) | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 2100 | + | 2100 | x | + | 23100 | ( | 1 | + | x | ) | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 2100 | + | 2100 | x | + | 23100 | × | 1 | ( | 1 | + | 2 | x | ) | + | 23100 | x | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 2100 | + | 2100 | x | + | 23100 | ( | 1 | + | 2 | x | ) | + | 23100 | x | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 2100 | + | 2100 | x | + | 23100 | × | 1 | + | 23100 | × | 2 | x | + | 23100 | x | ( | 1 | + | 2 | x | ) | + | 8400 |
| = | 2100 | + | 2100 | x | + | 23100 | + | 46200 | x | + | 23100 | x | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 25200 | + | 48300 | x | + | 23100 | x | ( | 1 | + | 2 | x | ) | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 25200 | + | 48300 | x | + | 23100 | x | × | 1 | + | 23100 | x | × | 2 | x | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 25200 | + | 48300 | x | + | 23100 | x | + | 46200 | x | x | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 25200 | + | 71400 | x | + | 46200 | x | x | + | 8400 | ( | 1 | + | 2 | x | ) |
| = | 25200 | + | 71400 | x | + | 46200 | x | x | + | 8400 | × | 1 | + | 8400 | × | 2 | x |
| = | 25200 | + | 71400 | x | + | 46200 | x | x | + | 8400 | + | 16800 | x |
| = | 33600 | + | 88200 | x | + | 46200 | x | x |
| 33600 | + | 88200 | x | + | 46200 | x | x | = | 15 8 | × | 21700 |
| Right side of the equation = | 81375 2 |
| 33600 | + | 88200 | x | + | 46200 | x | x | = | 81375 2 |