a | + | ( | a | + | 2 | ) | + | ( | 2 | a | − | 23 | ) | + | ( | 52 | − | a | ) | = | 28 | × | 4 |
Left side of the equation = | a | + | a | + | 2 | + | ( | 2 | a | − | 23 | ) | + | ( | 52 | − | a | ) |
= | 2 | a | + | 2 | + | ( | 2 | a | − | 23 | ) | + | ( | 52 | − | a | ) |
= | 2 | a | + | 2 | + | 2 | a | − | 23 | + | ( | 52 | − | a | ) |
= | 4 | a | − | 21 | + | ( | 52 | − | a | ) |
= | 4 | a | − | 21 | + | 52 | − | a |
= | 3 | a | + | 31 |
3 | a | + | 31 | = | 28 | × | 4 |
Right side of the equation = | 112 |
3 | a | + | 31 | = | 112 |
3 | a | = | 112 | − | 31 |
3 | a | = | 81 |
a | = | 81 | ÷ | 3 |
= | 81 | × | 1 3 |
= | 27 | × | 1 |
a | = | 27 |