2 15/2 х-3* (5+11/18 х) = 19

2 15/2 х - 15-33/18 х = 19

19/2 х -33/18 х = 19+15

171/18 х-33/18 х = 34

138/18 х = 34

х = 34:138/18

х = 34*18/138

х = 102/23 = 4 10/23 

Проверяем:

19/2*102/23 - 3*(5+11/18*102/23) = 969/23 - 3*(5+561/207)= 969/23-3*1596/207 =

= 969,23-4788/207 = 42,13-23,13 = 19 

Ответ: 4 10/23.