for
|a|<b
assume
-b<a<b
so
add 5 to both side
|-2-8x|<66
assume
-66<-2-8x<66
add 2 to both sides
-64<-8x<68
divide everyboy by -8, don't forget to flip sign
8>x>-8.5
-8.5<x<8
the solution is all numbers between -8.5 and 8, not including -8.5 and 8
in interval notation: (-8.5,8)
or
S={x|-8.5<x<8}
