Ответ:

Пошаговое объяснение:

3 1/3 - ( 4 1/5х + х ) : 5 4/7 = 8/15

10/3 - ( 21/5х + х) : 39/7 = 8/15

10/3 - 26/5х : 39/7 = 8/15

10/3 - 26/5х * 7/39 = 8/15

10/3 - 2/5х * 7/3 = 8/15

10/3 - 14/15х = 8/15 (*15)

50 - 14х = 8

-14х = 8 - 50

-14х = - 42

х = 3