900 | ÷ | x | = | 1200 | ÷ | ( | x | + | 20 | ) |
Multiply both sides of the equation by: | x | , | ( | x | + | 20 | ) |
900 | ( | x | + | 20 | ) | = | 1200 | x |
900 | x | + | 900 | × | 20 | = | 1200 | x |
900 | x | + | 18000 | = | 1200 | x |
900 | x | − | 1200 | x | = | - | 18000 |
- | 300 | x | = | - | 18000 |
18000 | = | 300 | x |
300 | x | = | 18000 |
x | = | 18000 | ÷ | 300 |
= | 18000 | × | 1 300 |
= | 60 | × | 1 |
x | = | 60 |