Выражения: 1) 2x-(4x+6)-7 2)-3(y+2)-0.2(30y-40) решить уравнения: 1)4x-1=-7x+21 2)-3(x+1)=6x-17 3)9x/7=x-2/4(/-это дробь)

1) 2x-(4x
+6)-7 = 2х-4х-6-7 = -2х-13
2) -3(y+2)-0.2(30y-40) = -3у-6-6у+8 = 2-9у

1) 4x-1 = -7x+21
11х = 22
х = 2
2) -3(x+1) = 6x-17
-3х-3 = 6х-17
3х = -14
х = -3/14
3) 9x/7 = x-2/4
36х = 7х-14
29х = -14
х = -14/29