9) 9[x]-6=0
9[x]=6
[x]=2/3
x=2/3, x=-2/3
10) 8/x=6/5
6x=40
x=40/6
x=20/3
x=6 2/3
19) 2m/3 - 4m/5 =3
10m-12m=45
-2m=45
m=-45/2
m= -22,5
20) 4a/9 - 1 = 5a/12
16a - 36 = 15a
16a - 15a = 36
a=36
21) 3-3x+5x+10=1-4x
13+2x=1-4x
2x+4x=1-13
6x=-12
x=-2
22) 6-3x-5x-4=0.4-16x
2-8x=0.4-16x
16x-8x=0.4-2
8x=-1.6
x= -0.2
23) 6-10p=4-4p-1
6-10p=3-4p
-10p+4p=3-6
-6p=-3
p=0.5
24) y-0.5-0.5+0.2y+1=0
1.2y+0=0
1.2y=0
y=0
25) -20+8m+3m-12=12-6m-5m
-32m+11m=12-11m
11m+11m=12+32
22m=44
m=2
26) 0.9x-0.3+0.2=0.5-x-0.1
0.9x-0.1 = 0.4-x
0.9x+x=0.4+0.1
1.9x=0.5
x= 5/19
30 - 2, 3, 5, 6, 10, 15.
15 - 3, 5
23 - нет
80 - 2, 4, 5, 8, 10, 16, 20, 40