Question 142095
[x-5]=15
x-5=15 or x-5=-15
gives x=20 or x=-10

3[x]-5=1
3|x|=6
|x|=2
gives x=2 or x=-2

[x]+5=15
|x|=10
gives x=10 or x=-10
 
3[2x-5]-2=7
3|2x-5|=9
|2x-5|=3
2x-5=3 or 2x-5=-3
2x=8  or 2x=2
gives x=4 or x=1