hoganjohnson007 1) 1.2x+4.2=x-0.8
      1.2x-x=-4.2-0.8
       0.2x=-5
       x=-25 
 

lollylolly 3(0,4х + 1,4)=х-0,8
1,2х+4,2=х-0,8
1,2х-х=-0,8-4,2
0,2х=-5
х=-5:0,2
х=-25

х-1 2/7 =4х+2 5/14
х-9/7=4х+33/14
х-4х=33/14+9/7
-3х=33/14+18/14
-3х=51/14
х=51/14:(-3)=51/14*(-1/3)
х=-17/14=-1 3/14