A point charge with charge q1 is held stationary at the origin. A second point charge with charge q2 moves from the point (x1, 0) to the point (x2,y2). Please use k for Coulomb's constant rather than writing it out as (1/4π?0).
How much work W is done by the electrostatic force on the moving point charge?
Express your answer in joules. Use k for Coulomb's constant.