2:(3-2x) = 1
2 = 3-2х
2х = 3-2
2х=1
х = 1:2
х = 0,5
3(5x+2)=12
15х + 6 = 12
15х = 12 - 6
15х = 6
х = 6:15
х = 0,4
21(x-3)=12
21х - 63 =12
21х = 12+63
21х = 75
х = 75:21
х =15/7 = 2 1/7
21(3-x)=12
63 - 21х = 12
-21х = 12 - 63
-21х = -51
х = -51 : (-21)
х = 17/7 = 2 3/7
21x-3=12
21х = 12 + 3
21х = 15
х = 15:21
х = 5/7
21:(x-3)=7
21 = 7•(х-3)
7х - 21 = 21
7х = 21 +21
7х = 42
х = 42:7
х = 6
7(3x+1)=-14
21х + 7 = -14
21х = -14 - 7
21х = - 21
х = -21 : 21
х = -1
3x+12-2x=11
3х - 2х = 11 - 12
х = -1
5x-2=13
5х = 13 + 2
5х = 15
х = 15:5
х = 3
5(x-2)=15
5х - 10 = 15
5х = 15 + 10
5х = 25
х = 25 : 5
х = 5
(5/8-3/8+3/4)*8=
1)5/8-3/8=2/8,1/4
2)3/4+1/4=4/4=1
3)1*8=8
Между -3 и -4.
<span>вроде так
</span>
28142см=281м4дм2см=2814дм2см