x | + | 30 | − | 20 | = | ( | x | − | 20 | ) | × | 4 |
Left side of the equation = | x | + | 10 |
x | + | 10 | = | ( | x | − | 20 | ) | × | 4 |
Right side of the equation = | x | × | 4 | − | 20 | × | 4 |
= | x | × | 4 | − | 80 |
x | + | 10 | = | 4 | x | − | 80 |
x | − | 4 | x | = | - | 80 | − | 10 |
- | 3 | x | = | - | 80 | − | 10 |
- | 3 | x | = | - | 90 |
90 | = | 3 | x |
3 | x | = | 90 |
x | = | 90 | ÷ | 3 |
= | 90 | × | 1 3 |
= | 30 | × | 1 |
x | = | 30 |