Упростите алгебраическое выражение:

a) 27-5 (2-6b) - 14b+9

b) - 4 (7z-23+4d) - 2 (d-z)

c) 5k - (6k - (2k-3))

d) 7y - (4y - ((z-3y) - 8z)

A) 27-5 (2-6b) - 14b+9 = 27-10+30b-14b+9 = 26+16b

b) - 4 (7z-23+4d) - 2 (d-z) = - 28z+92-16d-2d+2z = - 26z+92-18d

c) 5k - (6k - (2k-3)) = 5k - (6k-2k+3) = 5k-6k+2k-3 = k-3

d) 7y - (4y - ((z-3y) - 8z) = 7y - (4y - (z-3y-8z)) = 7y - (4y-z+3y+8z) = 7y-4y+z-3y-8z = - 7z