уравнения
5x-4+2x=7(x-3)
7-0.2x-(21.28-1.6)=0
1/2x-3-(2-1/3x)=0
6/5-0.5x-0.4+2/5x=0
1) 5х-4+2х=7(х-3)
5х-4+2х=7х-3
5х+2х-7х=-3+4
х=1
2) 7-0.2x-(21.28-1.6)=0
7-0.2x-21.28+1.6=0
-0.2х=-1.6+21.28-7
-0.2х = 12.68
х= 12.68 : (- 0.2)
х=-63.4
3)1/2x-3-(2-1/3x)=0
1/2х-3-2+1/3х=0
1/2х+1/3=3+2
5/6х=5
х=5: 5/6
х=6
4)6/5-0.5x-0.4+2/5x=0
-0.5х+2.5х=-6/5+0.4
2х=-0.8
х=-0.8 : 2
х= -0.4