| 2 | ( | 3 | z | + | 35 | − | z | ) | = | 4 | ( | 4 | z | + | 70 | − | 2 | z | ) |
| Left side of the equation = | 2 | × | 3 | z | + | 2 | × | 35 | − | 2 | z |
| = | 6 | z | + | 70 | − | 2 | z |
| = | 4 | z | + | 70 |
| 4 | z | + | 70 | = | 4 | ( | 4 | z | + | 70 | − | 2 | z | ) |
| Right side of the equation = | 4 | × | 4 | z | + | 4 | × | 70 | − | 4 | × | 2 | z |
| = | 16 | z | + | 280 | − | 8 | z |
| = | 8 | z | + | 280 |
| 4 | z | + | 70 | = | 8 | z | + | 280 |
| 4 | z | − | 8 | z | = | 280 | − | 70 |
| - | 4 | z | = | 280 | − | 70 |
| - | 4 | z | = | 210 |
| - | 210 | = | 4 | z |
| 4 | z | = | - | 210 |
| z | = | - | 210 | ÷ | 4 |
| = | - | 210 | × | 1 4 |
| = | - | 105 | × | 1 2 |
| z | = | - | 105 2 |
| z | = | - 52.5 |