6x-2(x+3)=3(x+0.4)
6x-2x-6=3x+1.2
4x-3x=6+1.2
x=7.2
2.35/(0.7x+0.12)=5
0.7x+0.12=2.35/5
0.7x=0.47-0.12
0.7x=0.35
x=0.5