| ( | 109 2000 | − | 2 | x | ) | ( | 109 2000 | − | 2 | x | ) | = | 109 2 | ( | x | + | 3 500 | ) | ( | x | + | 9 10000 | ) |
| Left side of the equation = | 109 2000 | ( | 109 2000 | − | 2 | x | ) | − | 2 | x | ( | 109 2000 | − | 2 | x | ) |
| = | 109 2000 | × | 109 2000 | − | 109 2000 | × | 2 | x | − | 2 | x | ( | 109 2000 | − | 2 | x | ) |
| = | 11881 4000000 | − | 109 1000 | x | − | 2 | x | ( | 109 2000 | − | 2 | x | ) |
| = | 11881 4000000 | − | 109 1000 | x | − | 2 | x | × | 109 2000 | + | 2 | x | × | 2 | x |
| = | 11881 4000000 | − | 109 1000 | x | − | 109 1000 | x | + | 4 | x | x |
| = | 11881 4000000 | − | 109 500 | x | + | 4 | x | x |
11881 4000000 | − | 109 500 | x | + | 4 | x | x | = | 109 2 | ( | x | + | 3 500 | ) | ( | x | + | 9 10000 | ) |
| Right side of the equation = | 109 2 | x | ( | x | + | 9 10000 | ) | + | 109 2 | × | 3 500 | ( | x | + | 9 10000 | ) |
| = | 109 2 | x | ( | x | + | 9 10000 | ) | + | 327 1000 | ( | x | + | 9 10000 | ) |
| = | 109 2 | x | x | + | 109 2 | x | × | 9 10000 | + | 327 1000 | ( | x | + | 9 10000 | ) |
| = | 109 2 | x | x | + | 981 20000 | x | + | 327 1000 | ( | x | + | 9 10000 | ) |
| = | 109 2 | x | x | + | 981 20000 | x | + | 327 1000 | x | + | 327 1000 | × | 9 10000 |
| = | 109 2 | x | x | + | 981 20000 | x | + | 327 1000 | x | + | 2943 10000000 |
| = | 109 2 | x | x | + | 7521 20000 | x | + | 2943 10000000 |
11881 4000000 | − | 109 500 | x | + | 4 | x | x | = | 109 2 | x | x | + | 7521 20000 | x | + | 2943 10000000 |