Odpowiedź:
1. 9x - 6 = 39
9x = 39 + 6
9x = 45 | :9
x = 5
2. 12x - 15 = 33
12x = 33 +15
12x = 48 | :12
x = 4
3. 2x - 9 = 6 - 3x
2x + 3x = 6 + 9
5x = 15 |:5
x = 3
4. 3x - 5 = 5(x - 5)
3x - 5 = 5x -25
-5 + 25 = 5x - 3x
20 = 2x | :2
10 = x
5. 2x + 5(16 - x) = 50
2x + 80 - 5x = 50
2x - 5x = 50 - 80
-3x = -30 | :-3
x = 10
Szczegółowe wyjaśnienie: