Question

3)a - ((b - c) - d) =
4)a-(b+(c-(d-k)))=

Answer 1

А - (( b - c ) - d ) = a - ( b - c - d ) = a - b + c + d
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a - ( b + ( c - ( d - k ))) = a - ( b + ( c - d + k )) = a - ( b + c - d + k ) = a - b - c + d - k

Answer 2

Решение смотри на фотографии