Ответ:

Пошаговое объяснение:

1)5/8-7/9 = 45/72 - 56/72 = -(56/72 - 45/72) = -11/72

2)6/7-(-1/7) = 6/7 + 1/7 = 7/7 = 1

3)-1/7-1/14 = -(2/14 + 1/14) = -3/14

4)-5/21-(-1/7) = -(5/21 - 3/21) = -2/21

5)-5,9-6,1 = -(5,9+6,1) = -12

6)8-10,24 = -(10,24 - 8) = -2,24