5х-3,4/ 0,75= 2/5 5х- 3,4= 2/5* 0,75 5х-3,4= 2/5*3/4 5х= 3/10+ 3 2/5 5х= 3 7/10 х= 3 7/10: 5/1 х=37/10* 1/5 х=37/50 х= 0,74