6-3(х+1)=7-х
6-3х-3=7-х
-3х+х=7-6+3
-2х=4
х=4:(-2)
х=-2
2.8-х=8(х+2.8)
2.8-х=8х+22.4
-х-8х=22.4-2.8
-9х=19.6
х=-2.18