а) 30 + 5(3x - 1) = 35x - 25

30 + 15x - 5 = 35x - 25

15x + 25 = 35x - 25

15x - 35x = -25 - 25

-20x = -50

x = 50/20 = 5/2 = 2 1/2

б) 10x - 5 = 6(8x + 3) - 5x

10x - 5 = 48x + 18 - 5x

10x - 5 = 43x + 18

10x - 43x = 18 + 5

-33x = 23

x = -23/33

)))))))))))))))))))......