Imagine a very large nonconducting plate that has a uniform surface charge density σ =1 μC/m2; it also shows a point charge Q = -3 μC at distance d = 0.3 m from the plate. Both are fixed in place. We choose the origin of an x-axis at Q.

Question

Imagine a very large nonconducting plate that has a uniform surface charge density σ =1 μC/m2; it also shows a point charge Q = -3 μC at distance d = 0.3 m from the plate. Both are fixed in place. We choose the origin of an x-axis at Q.
At what positive coordinate on the x-axis (other than infinity) is the net electric field Enet=0?

At what negative coordinate on the x-axis (other than infinity) is the net electric field Enet=0?