| ( | 7 | x | + | 70 | ) | ÷ | ( | 4 | x | + | 70 | ) | = | 8 | ÷ | 5 |
| Multiply both sides of the equation by: | ( | 4 | x | + | 70 | ) |
| ( | 7 | x | + | 70 | ) | = | 8 | ÷ | 5 | × | ( | 4 | x | + | 70 | ) |
| 7 | x | + | 70 | = | 8 | ÷ | 5 | × | ( | 4 | x | + | 70 | ) |
| 7 | x | + | 70 | = | 8 | ÷ | 5 | × | 4 | x | + | 8 | ÷ | 5 | × | 70 |
| 7 | x | + | 70 | = | 32 5 | x | + | 112 |
| 7 | x | − | 32 5 | x | = | 112 | − | 70 |
3 5 | x | = | 112 | − | 70 |
3 5 | x | = | 42 |
| x | = | 42 | ÷ | 3 5 |
| = | 42 | × | 5 3 |
| = | 14 | × | 5 |
| x | = | 70 |