| ( | 30 | − | 20 | x | ) | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 | ( | 30 | − | 20 | x | ) | + | 144 | ( | 10 | x | − | 6 | ) | = | 0 |
| Left side of the equation = | 30 | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 | ( | 30 | − | 20 | x | ) | + | 144 | ( | 10 | x | − | 6 | ) |
| = | 30 | × | 18 | ( | 6 | − | 10 | x | ) | − | 30 | × | 15 | x | ( | 6 | − | 10 | x | ) | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 |
| = | 540 | ( | 6 | − | 10 | x | ) | − | 450 | x | ( | 6 | − | 10 | x | ) | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 | ( | 30 | − | 20 | x | ) | + | 144 |
| = | 540 | × | 6 | − | 540 | × | 10 | x | − | 450 | x | ( | 6 | − | 10 | x | ) | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) |
| = | 3240 | − | 5400 | x | − | 450 | x | ( | 6 | − | 10 | x | ) | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 | ( | 30 | − | 20 | x | ) |
| = | 3240 | − | 5400 | x | − | 450 | x | × | 6 | + | 450 | x | × | 10 | x | − | 20 | x |
| = | 3240 | − | 5400 | x | − | 2700 | x | + | 4500 | x | x | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) |
| = | 3240 | − | 8100 | x | + | 4500 | x | x | − | 20 | x | ( | 18 | − | 15 | x | ) | ( | 6 | − | 10 | x | ) | − | 36 | ( | 30 | − | 20 | x | ) |
| = | 3240 | − | 8100 | x | + | 4500 | x | x | − | 20 | x | × | 18 | ( | 6 | − | 10 | x | ) | + | 20 | x |
| = | 3240 | − | 8100 | x | + | 4500 | x | x | − | 360 | x | ( | 6 | − | 10 | x | ) | + | 300 | x | x |
| = | 3240 | − | 8100 | x | + | 4500 | x | x | − | 360 | x | × | 6 | + | 360 | x | × | 10 |
| = | 3240 | − | 8100 | x | + | 4500 | x | x | − | 2160 | x | + | 3600 | x | x | + | 300 |
| = | 3240 | − | 10260 | x | + | 4500 | x | x | + | 3600 | x | x | + | 300 | x | x |
| = | 3240 | − | 10260 | x | + | 4500 | x | x | + | 3600 | x | x | + | 300 | x | x |
| = | 3240 | − | 10260 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 3240 | − | 10260 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 3240 | − | 10260 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 2160 | − | 9540 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 2160 | − | 9540 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 2160 | − | 9540 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| = | 1296 | − | 8100 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x |
| 1296 | − | 8100 | x | + | 4500 | x | x | + | 3600 | x | x | + | 1800 | x | x | = | 0 |