1. The problem statement, all variables and given/known data Charge q1= 8.5 nC is located at the coordinate system origin (0,0), while charge q2= -4.46 nC is located at (a,0), where a= 1.5 m. The point P has coordinates (a,b), where b=0.95 m. A third charge q3= 16.5 nC will b added later. It is a 3 part question, first asking for the Electric Potential at point P, then asking for the work done to bring q3 from infinity to point P, and then finding the total potential energy of the final configuration of three charges. 2. Relevant equations U=q*V= -W U=kq1q2/r Utotal= U1 + U1,2 + U1-2,3 3. The attempt at a solution The question is in three part. The first part I found the electric potential at point P, which is 0.83314271 V. The second part I found the work (W) it took to move q3 to point P, which is 1.3746*10-8 J. I understand that what we are doing is finding the work it takes to move the 3 charges to the point and the the Potential Energy of the first charge is 0 J. I know the answer, which is -28.9 J, but I don't know how to get there.