tolong......................

-10 >= 2x/3 + 20 >= 10

-10 >= 2x/3 + 20
-30 >= 2x + 60
-30 - 60 >= 2x
-90 >= 2x
-90/2 >= x
-45 >= x
x <= -45

2x/3 + 20 >= 10
2x + 60 >= 30
2x >= 30 - 60
2x >= -30
x >= -15

x <= -45 atau x >= -15