| 3 | ( | 22 | + | 4 | t | ) | + | 4 | ( | 29 | + | 6 | t | ) | + | 6 | ( | 9 | + | 2 | t | ) | = | 20 |
| Left side of the equation = | 3 | × | 22 | + | 3 | × | 4 | t | + | 4 | ( | 29 | + | 6 | t | ) | + | 6 | ( | 9 | + | 2 | t | ) |
| = | 66 | + | 12 | t | + | 4 | ( | 29 | + | 6 | t | ) | + | 6 | ( | 9 | + | 2 | t | ) |
| = | 66 | + | 12 | t | + | 4 | × | 29 | + | 4 | × | 6 | t | + | 6 | ( | 9 | + | 2 | t | ) |
| = | 66 | + | 12 | t | + | 116 | + | 24 | t | + | 6 | ( | 9 | + | 2 | t | ) |
| = | 182 | + | 36 | t | + | 6 | ( | 9 | + | 2 | t | ) |
| = | 182 | + | 36 | t | + | 6 | × | 9 | + | 6 | × | 2 | t |
| = | 182 | + | 36 | t | + | 54 | + | 12 | t |
| = | 236 | + | 48 | t |
| 236 | + | 48 | t | = | 20 |
| 48 | t | = | 20 | − | 236 |
| 48 | t | = | - | 216 |
| t | = | - | 216 | ÷ | 48 |
| = | - | 216 | × | 1 48 |
| = | - | 9 | × | 1 2 |
| t | = | - | 9 2 |
| t | = | - 4.5 |