ж) 4 ⋅ (x + (-6)) = 20
4 ⋅ (x - 6) = 20
x - 6 = 20 : 4
x - 6 = 5
x = 5 + 6
x = 11
з) y + 8y = -72
9y = -72
y = -72 : 9
y = -8
Ответ: ж) x = 11; з) y = -8.