Tìm x

a)  - 30 + (25 – x) = -1
b)  x – (12 – 25) = -8
c)   (x – 29) – (17 – 38) = - 9                                  
d)   5x – 15 = - 35 + x
e) (2x+ 1)3 = 729                           
f)       x.(x + 1) = 0