1. 9х+13=7х+5
9х-2х=5-13
7х=-7
Х=-1
2. 3(2х+5)+6=3
6х+15+6=3
6х+21=3
6х=3-21
6х=-18
Х=-3
3. 5х+18=7х+6(3х-7)
5х+18=7х+18х-42
5х+18=25х-42
5х-25х=-42-18
-30х=-60
Х=2
4. 3х-7(3х-4)=5(2х-7)
3х-21х+28=10х-35
-18х+28=10х-35
-18х-10х=-35-28
-28х=-63
Х=2,25
5. 13-3(5х+1)-6(4х-3)=5х
13-15х-3-24х+18=5х
28-39х=5х
5х+39х=28
44х=28
Х=7/11
6. 4(Х+2)-0,7=2(2х+4)+0,3
4х+8-0,7=4х+8+0,3
4х+7,3=4х+8,3
4х-4х=8,3-7,3