A positive charge +q1 is located to the left of a negative charge -q2. On a line passing through the two charges, there are two places where the total potential is zero. The first place is between the charges and is 4.4 cm to the left of the negative charge. The second place is 8.4 cm to the right of the negative charge.
(a) What is the distance between the charges?
(b) Find q1 / q2, the ratio of the magnitudes of the charges.
Please explain how to locate the where the total potential is zero.