Problem 6 Three charges, -4uC, 2uC and -6uC are placed at the corners of a rectangle, as shown in figure (17. Determine the electric field at point...

I need to get explanation for what charge wee consider for point P and how to solve it.

Problem 6Three charges, -4uC, 2uC and -6uC are placed at the corners of a rectangle, asshown in figure (17.58). Determine the electric field at point P.q, =-4MC4cm93=-6MC3cmq2 =2MCPFigure 17.58: Problem 6