Question

3-4 (z+1 )= 3z -(2+z)

Answer 1

3-4z-4=3z-2-z
-1-4z=2z-2
-4z=2z-1
-6z=-1
6z=1
z=1/6

Answer 2

Just so you know, you can plug exactly what you posted into wolfram alpha and it will give you the solution much more quickly.

http://www.wolframalpha.com/