9+7(-4+5)-7+99-2-6-7+9-8+8+7+6

Ответ:

1)

9 + 8 = 9 + 1 + 7 = 17

7 + 6 = 7 +3 + 3 = 13

8 + 5 = 8 + 2 +3 = 13

9 + 7 = 9 + 1 + 6 = 16

2)

7 + 4 = 3 + 8 = 11

4 + 9 = 6 + 7 = 13

6 + 9 = 8 + 7 = 15

9 + 9 = 9 + 9 = 18