-4,23(12Х-21)/13 - 9(7Х-5,1)/5 срочно!!!!

а)

3х-5х= -13+3

-2x = -10

x = -10 : (-2)

x = 5

б)

-7х+12х=8-23

5x = -15

x = -15 : 5

x = -3

в)

-5у-17у= -50+6

-22y = -44

y = -44 : (-22)

y = 2

г)

16х-7х= -42-39

9x = - 81

x = -81 : 9

x = -9