| ( | 3 20000 | − | x | ) | ( | 7 20000 | − | x | ) | = | ( | 7 50000 | − | x | ) | ( | 43 50000 | − | x | ) |
| Left side of the equation = | 3 20000 | ( | 7 20000 | − | x | ) | − | x | ( | 7 20000 | − | x | ) |
| = | 3 20000 | × | 7 20000 | − | 3 20000 | x | − | x | ( | 7 20000 | − | x | ) |
| = | 21 400000000 | − | 3 20000 | x | − | x | ( | 7 20000 | − | x | ) |
| = | 21 400000000 | − | 3 20000 | x | − | x | × | 7 20000 | + | x | x |
| = | 21 400000000 | − | 1 2000 | x | + | x | x |
21 400000000 | − | 1 2000 | x | + | x | x | = | ( | 7 50000 | − | x | ) | ( | 43 50000 | − | x | ) |
| Right side of the equation = | 7 50000 | ( | 43 50000 | − | x | ) | − | x | ( | 43 50000 | − | x | ) |
| = | 7 50000 | × | 43 50000 | − | 7 50000 | x | − | x | ( | 43 50000 | − | x | ) |
| = | 301 2500000000 | − | 7 50000 | x | − | x | ( | 43 50000 | − | x | ) |
| = | 301 2500000000 | − | 7 50000 | x | − | x | × | 43 50000 | + | x | x |
| = | 301 2500000000 | − | 1 1000 | x | + | x | x |
21 400000000 | − | 1 2000 | x | + | x | x | = | 301 2500000000 | − | 1 1000 | x | + | x | x |