Ответ:

(-3 2/3-5 7/9)-(2 1/8-3 7/12)

(-(3 2/3+5 7/9))-(17/8-43/12)

(-(*3+5)+(2/3+7/9)))-(-35/24)

(-(8+1 4/9))+35/24

(-(8+1+4/9))+35/24

(-(9+4/9))+35/24

(-9 4/9)+35/24

-9 4/9+35/24

-85/9+35/24

-575/72