-6<3(x-1)<9 kak tolong dibantu cara penyelesaian

-6 < 3(x - 1) < 9
-6 ÷ 3 < 3(x - 1) ÷ 3 < 9 ÷ 3
-2 < x - 1 < 3
-2 + 1 < x - 1 + 1 < 3 + 1
-1 < x < 4

HP = {x | -1 < x < 4}