a) 0,12=12/100=6/50=3/25
3x=3/25+6 amplificãm pe 6 cu 25
3x= 3/25+150/25
3x=153/25
x=153/25×1/3
x=51/25=2,04
b) 3,2=32/10=16/5
-4x= -16/5
x= 16/5×1/4
x=4/5
c) 0,4x=5-3,8
0,4x=1,2
1,2=12/10=6/5
0,4=4/10=2/5
x=6/5×5/2
x=3
d) 1,2^2=1,44=144/100
0,08=8/100
2/3x=144/100-8/100
2/3x=136/100
x=136/100×3/2
x=204/100=2,04