| 2 | ( | 5 | + | x | + | 12 | ) | = | 50 | + | 212 | − | 2 | x |
| Left side of the equation = | 2 | × | 5 | + | 2 | x | + | 2 | × | 12 |
| = | 10 | + | 2 | x | + | 24 |
| = | 34 | + | 2 | x |
| 34 | + | 2 | x | = | 50 | + | 212 | − | 2 | x |
| Right side of the equation = | 262 | − | 2 | x |
| 34 | + | 2 | x | = | 262 | − | 2 | x |
| 2 | x | + | 2 | x | = | 262 | − | 34 |
| 4 | x | = | 262 | − | 34 |
| 4 | x | = | 228 |
| x | = | 228 | ÷ | 4 |
| = | 228 | × | 1 4 |
| = | 57 | × | 1 |
| x | = | 57 |