9. 15-8 60-50 6+6-10 27-27 13-8 30+40 7+7-10 43+0

15 - 8 = 7

13 - 8 = 5

60 - 50 = 10

30 + 40 = 70

6 + 6 - 10 = 12 - 10 = 2

7 + 7 - 10 = 14 - 10 = 4

27 - 27 = 0

43 + 0 = 43