9 целых 5/36-х=2 целых 4/9, х-5 целых 17/60=7 целых 9/20

9 5/36 - x = 2 4/9
x = 9 5/36 - 2 4/9
x = (9-2) (5*1 - 4*4)/36
x = (9-2) (5 - 20)/36
x = 7 (-11/36) это НЕ то же, что и (-7 11/36)
x = 7*36/36 - 11/36
x = (252 - 11)/36
x = 241/36
x = 6 25/36

Ответ: x = 6 25/36

Проверка:
9 5/36 - 7 (-11/36) = (9 - 7) (5/36 -(- 11/36)) =2 (5/36 + 11/36) = 2 16/36 = 2 (4*4)/(9*4) = 2 4/9
или
9 5/36 - 6 25/36 = (9 - 6) (5/36 - 25/36)) = 3 (5 - 25/36)) = 3 (-20/36) = 3*36/36 - 20/36 = (108-20)/36 = 88/36 = 2 16/36 = 2 4/9

x - 5 17/60 = 7 9/20
x = 7 9/20 + 5 17/60
x = (7 + 5) (9/20 + 17/60)
x = 12 (9*3/60 + 17*1/60)
x = 12 (27/60 + 17/60)
x = 12 (27 + 17)/60
x = 12 44/60
x = 12 (11*4)/(15*4)
x = 12 11/15

Ответ: x = 12 11/15

Проверка:
12 44/60 - 5 17/60 = (12-5) (44/60 - 17/60) = 7 27/60 = 7 (9*3)/(20*3) = 7 9/20