| 2021 | ( | X | − | 2 | ) | − | ( | 1 | − | 3 | X | ) | = | 2019 | X | + | 2 |
| Left side of the equation = | 2021 | X | − | 2021 | × | 2 | − | ( | 1 | − | 3 | X | ) |
| = | 2021 | X | − | 4042 | − | ( | 1 | − | 3 | X | ) |
| = | 2021 | X | − | 4042 | − | 1 | + | 3 | X |
| = | 2024 | X | − | 4043 |
| 2024 | X | − | 4043 | = | 2019 | X | + | 2 |
| 2024 | X | − | 2019 | X | = | 2 | + | 4043 |
| 5 | X | = | 2 | + | 4043 |
| 5 | X | = | 4045 |
| X | = | 4045 | ÷ | 5 |
| = | 4045 | × | 1 5 |
| = | 809 | × | 1 |
| X | = | 809 |