4(z – 6) – 3(z – 3) = 8
4z - 24 - 3z + 9 = 8
z - 15 = 8
z = 23
Ответ: z = 23
б)-6(6 – x) – 5x = 18
-36 + 6x - 5x = 18
x = 18 + 36
x = 54
Ответ: x = 54
в)1/5 (5x – 10) – 2/9 (9x – 27) = 9
x - 2 - 2x + 6 = 9
-x + 4 = 9
-x = 5
x = -5
Ответ: x = -5
г)4,2(3z – 5) – 1,4(5z – 3) = 5,6
12,6z - 21 - 7z + 4,2 = 5,6
5,6z - 16,8 = 5,6
5,6z = 22,4
z = 4
Ответ: z = 4