pertidaksamaan,, caranya juga y

8) -1 < 2/3 (2x - 1) ≤ 1 ======> kalau 3/2
-1 . 3/2 < 2/3 (2x - 1) . 3/2 ≤ 1 . 3/2
-3/2 < (2x - 1) ≤ 3/2 =======> tambah 1
-3/2 + 1 < 2x - 1 + 1 ≤ 3/2 + 1
-1/2 < 2x ≤ 5/2 ===========> kali 1/2
-1/2 . 1/2 < 2x . 1/2 ≤ 5/2 . 1/2
-1/4 < x ≤ 5/4

9) -5 < 3 - 2x < 1 =====> kurangi 3
-5 - 3 < 3 - 2x - 3 < 1 - 3
-8 < -2x < -2 =========> kali -1/2
-8 . -1/2 > -2x . -1/2 > -2 . -1/2
4 > x > 1
1 < x < 4

3x - 2 > 8 - 2x
3x + 2x > 8 + 2
5x > 10
x > 2

Irisan : 1 < x < 4 dengan x > 2 adalah 2 < x < 4 = (2, 4)