How to Plot Electric Potential and Field with Given Boundary Conditions?

[TomorrowS]

To plot the electric potential and electric field, we should find the function about x, y.The attempt at a solution
I try to get E(ΔV/d) in x-axis, but no more development, to y and diagonal direction.

plus, Let me know how to use V=1, -1 plate, and V=0(boundary).

 

[FactChecker]

It just asks to draw the answer, so I think that trying to determine a "function about x, y" is more than it is asking for. Also, I don't see any conformal mapping that would give you such a function. You can use symmetry to determine some values on the y axis. I don't know what type of "drawing" would work well.