A point charge of -8.4 µC is at the origin.

a)What is the electric potential due to this charge at (x,y) = (3.5 m, 0 m)

b) What is the electric potential due to this charge at (x,y) = (-3.5 m, 0 m)

c) What is the electric potential to this charge at (x,y) =(3.5 m, -3.5 m)?

For a & b i got -2.1600e4 then Distance between q & the given point, d = v2 * 3.5 m...what is v2 so that i can figure out the distance for part c?