How Do You Calculate Electric Potential Energy in a Multi-Charge System?

[synergix]

Homework Statement

Compute the electric potential energy for the charge configuration shown below.
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Homework Equations

PE=-W=qV=q(vb-va)

The Attempt at a Solution

It is assumed that the charges are being brought in from infinity the -3.0 micro coulomb charge is charge one, 5.0 micro coulomb charge is number 3

TPE=PE11+PE12+(PE13+PE23)
TPE= 0J+[(q1KQ2)/r2] + [(q1KQ3)/r1 + (q2KQ3)/r3]

where q1 is charge 1, q2 and Q2 are charge 2, Q3 is charge 3, r1 is the distance between q1 and Q3, r2 is the distance between charge 1 and 2, r3 is the distance between q2 and Q3.

am I on the right track can I simply solve this equation to get the right answer?

 

[LowlyPion]

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