**Electric potential energy** is a scalar quantity. In the formula, the values of charges q_{1} and q_{2} are kept with sign. If there are two or more charges in a system, then finding the electric potential energy of each pair of charges and adding them by algebraic method.

Example : If three charges q_{1} , -q_{2} , +q_{3} are at three corners of a triangle, then the electric potential energy of the system