Question

-6≤2x-4<8

Answer 1

add 4 and then divide by 2 as follows:

-6 =<2x-4< 8
+4 +4 +4
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Answer 2

I separate the inequalities to solve it.
-6 <= 2x (divide by 2)
-6/2 <= x
-3 <= x

2x - 4 < 8 (add 4 to both sides)
2x < 12 (divide by 2)
x < 6

now we have : x >= -3 and x < 6
This can be written like this : -3 <= x < 6