With your values you get:
The axis of symmetry is a parallel of the y-axis (x-coordinates of F and V are equal) and therefore the directrix must be perpendicular to the y-axis.
The distance between F and V is 3. Thus the directrix has the equation y = 7.
Since F is below V the parabola opens down. The parameter p = 3 (=distance between F and V). The general equation of such a parabola is:
Therefore the equation of the parabola is:
The endpoints of the latus rectum have the coordinates . Therefore the points are at (-4, 1) and (8, 1)