I hope this helps you
5+1-6х+4=0
-6х+1=0
D=36-36=0
x=6/18=1/3
-2<6x+7<1
6х+7>-2
6х+7+2>0
6х>-9
х>-1,5
6х+7<1
6х+7-1<0
6х<-6
х<1