1/2{1/3[1/4(1/5x-1)-6]＋4}=1
1/3[1/4(1/5x-1)-6]＋4=2
1/3[1/4(1/5x-1)-6]=-2
1/4(1/5x-1)=0
1/5x-1=0
x=5