7х-2,8=1-3 (4-х)
7x - 2,8 = 1 - 12 + 3x
7x -3x = 1 - 12 + 2,8
4x = -8,2
x = -2,05
7х-2,8-1+12-3х=0
4х+8,2=0
4х=-8,2
х=-2,05
7х-2,8=1-3 (4-х)
7x - 2,8 = 1 - 12 + 3x
7x -3x = 1 - 12 + 2,8
4x = -8,2
x = -2,05
7х-2,8-1+12-3х=0
4х+8,2=0
4х=-8,2
х=-2,05