10-5+4=;10-(5+4)=;6+(20-11)=;9-7+2=;9-(7+2)=;(9+6)-11=

здравствуй.

10 - 5 + 4 = 5 + 4 = 9

10 - (5 + 4) = 10 - 9 = 1

6 + (20 - 11) = 6 + 9 = 15

9 - 7 + 2 = 2 + 2 = 4

9 - (7 + 2) = 9 - 9 = 1

(9 + 6) - 11 = 15 - 11 = 4

удачи в учёбе.