(21-48) Determine the direction and magnitude of the electric field at the point P shown in Fig. 21-

(21-48) Determine the direction and magnitude of the electric field at the point P shown in Fig. 21-64. The two charges are separated by a distance of 2a. Point P is on the perpendicular bisector of the line joining the charges, a distance x from the midpoint between them. Express your answers in terms of Q, x, a, and k.