1)-5х-6х=-10+9
-11х=-1
х=-1/11
2)4х=7+12х+9
4х-12х=16
-8х=16
х=-2
3)15х+5+2х=4х+5
15х+2х-4х=5-5
13х=0
х=-13
4)21х-3-30х-12=3
21х-30х=3+3+12
-9х=18
5)3х-10х-15=15-24х+4
3х-10х+24х=15+4+15
17х=34
х=2
6)1.9х+2.1-0.3х=2.1-0.28
1.9х-0.3х=2.1-0.28-2.1
0.6х=-0.28
х=-0.5
1)-5х-6х=-10+9
-11х=-1
х=-1/11
2)4х=7+12х+9
4х-12х=16
-8х=16
х=-2
3)15х+5+2х=4х+5
15х+2х-4х=5-5
13х=0
х=-13
4)21х-3-30х-12=3
21х-30х=3+3+12
-9х=18
х=-2
5)3х-10х-15=15-24х+4
3х-10х+24х=15+4+15
17х=34
х=2
6)1.9х+2.1-0.3х=2.1-0.28
1.9х-0.3х=2.1-0.28-2.1
0.6х=-0.28
х=-0.5