а) 2 (2х - 3) + 7х - 13 + 3 ( 5 - 2х) = 6х - 6
4х - 6 + 7х - 13 + 15 - 6х = 6х - 6
5х + 2 = 6х
5х - 6х = - 2
- х = - 2
х = 2
б) 4 ( х - 2) + 5 ( 2х - 5) + 4х - 1 = 80 - 20х
4х - 8 + 10х - 25 + 4х - 1 = 80 - 20х
18х - 34 = 80 - 20х
18х + 20х = 80 + 34
38х = 114
х = 3
1)9х-9=х+15
8х=24
х=3
2)45/6=10х/24
45*24=6*10х
45*4=10х
45*2=5х
9*2=х
х=18