Electric flux from line charge through plane strip

Natique

Hey there! :)
1. The problem statement, all variables and given/known data
A uniform line charge with linear charge density = 6nC/m is situated coincident with the x-axis. Find the electric flux per unit length of line passing through a plane strip extending in the x direction with edges at y=1, z=0, and y=1, z=5.
The final answer is 1.31 nC/m. Only problem is I have no idea how to get it.


2. Relevant equations
integral of D.ds over a closed surface = electric flux = Q enclosed.


3. The attempt at a solution
Attached

I'm sure the answer is really obvious, but I'm just not seeing it. I attached two solutions, but I actually attempted about 6 other ways, all of which are so pathetically illogical I'd really rather not post them. Anyway any help would be reeeeeeeeally appreciated! And it's not a homework question, so it'd be awesome if you could walk me through it step by step.

Edit: Do you think this should be in the advanced physics subforum? :S

Attached Files

my solution.zip (6.4 KB, 42 views)