1)17-5(2х+7)=4(5х-3) 2)3х-5(6х-7)=5-6(2х-5) 3)-3(х+12)-2(х-18)=-5х 4)8х+12=5х+3 5)3(2х+1)+7=4 6)6+3(5х-7)=4х+7 7)3(7х-4)-4(6х+5)=х 8)3х-5(2х=3)-6(5х-4)=-28 9)3(х+21)+2(х-4)=5(х+11) 10)-3х-25=-6-7 11)6(3х-1)-6=4 12)9х+2=4(5х-3)-8 13)4-2(6х-5)=6(4х+3) 14)6(3х-4)-7(2х+5)=2х-1 15)2.3(х-0.3)+0.5х=2.8

1)
17-5(2х+7)=4(5х-3)
17-10x-35=20x-12
20x+10x=17-35+12
30x=-6
x=-6:30
x=-0,2 

2)
3х-5(6х-7)=5-6(2х-5)
3x-30x+35=5-12x+30
-12x-3x+30x=35-5-30
15x=0
x=0

3)
-3(х+12)-2(х-18)=-5х
-3x-36-2x+36=-5x
-3x-2x+5x=36-36
0=0 (x любое значение)

4)
8х+12=5х+3
8x-5x=3-12
3x=-9
x=-9:3
x=-3

5)
3(2х+1)+7=4
6x+3+7=4
6x+10=4
6x=4-10
6x=-6
x=-1

6)
6+3(5х-7)=4х+7
6+15x-21=4x+7
15x-4x=7-6+21
11x=22
x=22:11
x=2

7)
3(7х-4)-4(6х+5)=х
21x-12-24x-20=x
21x-24x-x=12+20
-4x=32
x=32:(-4)
x=-8

8)
3х-5(2х+3)-6(5х-4)=-28
3x-10x-15-30x+24=-28
3x-10x-30x=-28+15-24
-37x=37
x=-1

9)
3(х+21)+2(х-4)=5(х+11)
3x+63+2x-8=5x+55
3x+2x-5x=55-63+8
0=0 (x любое значение)

10)
-3х-25=-6-7
-3x=-6-7+25
-3x=12
x=12:(-3)
x=-4

11)
6(3х-1)-6=4
18x-6-6=4
18x=4+6+6
18x=16
x=16:18
x=8/9

12)
9х+2=4(5х-3)-8
9x+2=20x-12-8
9x-20x=-12-8-2
-11x=-22
x=22:11
x=2

13)
4-2(6х-5)=6(4х+3)
4-12x+10=24x+18
-12x-24x=18-4-10
-36x=4
x=4:(-36)
x=-1/9

14)
6(3х-4)-7(2х+5)=2х-1
18x-24-14x-35=2x-1
18x-14x-2x=-1+24+35
2x=58
x=58:2
x=29

15)
2.3(х-0.3)+0.5х=2.8
2,3x-0,69+0,5x=2,8
2,3x+0,5x=2,8+0,69
2,8x=3,49
x=3,49:2,8
x=1 69/280