General electric field question

[Jabababa]

Homework Statement

So let's say i have a positive test charge of P, and all the problems are to find electric field.

ex 1: If test charge P is in the middle of 2 positive charge, I find both Electric field strength and use the bigger number minus the smaller number.

ex 2: If test charge P is in the middle of a positive and negative charge, i find both Electric field strengths and add them together because the positive will repel and the negative will attract.

ex 3: if test charge P is at the very right side with 2 positive charges on the left both at different distance from the test charge. I add both Electric field together.

Did i nail the concept of this? And do i need to give a direction for electric field?

Homework Equations

The Attempt at a Solution

 

[ap123]

I would suggest that you draw a diagram for each of the situations and show the directions of the electric fields at the points you are interested in.
Then the total electric fields will be clearer.

You need to give directions for the electric fields since they are vector quantities.