| 45 | ( | 3 | x | − | 6 | ) | + | 25 | ( | 3 | x | − | 8 | ) | = | 0 |
| 方程左边 = | 45 | × | 3 | x | − | 45 | × | 6 | + | 25 | ( | 3 | x | − | 8 | ) |
| = | 135 | x | − | 270 | + | 25 | ( | 3 | x | − | 8 | ) |
| = | 135 | x | − | 270 | + | 25 | × | 3 | x | − | 25 | × | 8 |
| = | 135 | x | − | 270 | + | 75 | x | − | 200 |
| = | 210 | x | − | 470 |
| 210 | x | − | 470 | = | 0 |
| 210 | x | = | 0 | + | 470 |
| 210 | x | = | 470 |
| x | = | 470 | ÷ | 210 |
| = | 470 | × | 1 210 |
| = | 47 | × | 1 21 |
| x | = | 47 21 |
| x | = | 2.238095 |