Two charges q1= -25 C and q3= 4.0 C are placed 0.012 m apart. A third negative charge, q2 is placed a distance L from q1 as shown. If the net electric force on q2 is 0N what is the value of L?

Answer 1

as shown....?
you have to take the forces F12 adn F32 and add them as vectors.