Z-12=6
you take the 12 and add it to both sides making it look like:
z-12+12=6+12
which also looks like
z-0=6+12
z-0 = z
so now you have
z=6+12
6+12 = 18
SO Z=18!!!
your answer is 18
Maybe you should work on starting you're sentences.
I don’t quite understand what your asking... can’t you just draw the line longer?