7-3х=х+11
-3х-х=11-7
-4х=4
х=-4:4
х=-1 .
3х-15=х+3
3х-х=3+15
2х=18
х=18÷2
х=9
2 (х+3)=х+13
2х+6=х+13
2х-х=13-6
х=7
4 (5-х)=3х-1
20-4х=3х-1
-4х-3х=-1-20
-7х=-21
х=-21÷-7
х=3
3 (х-2)=х+4
3х-6=х+4
3х-х=4+6
2х=10
х=10÷2
х=5
5(х-1)=4х+3
5х-5=4х+3
5х-4х=3+5
х=8