SOLUTION: How do you find the vertex if the focus is (-4,4); directrix the line y= 2. I am completed lost.

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: How do you find the vertex if the focus is (-4,4); directrix the line y= 2. I am completed lost.      Log On


   

Question 469343: How do you find the vertex if the focus is (-4,4); directrix the line y= 2. I am completed lost.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the vertex and the focus both lie on the axis of symmetry, which is perpendicular to the directrix

so in this case, the axis of symmetry is ___ x = -4 (the x-coordinate of the focus)

the vertex lies midway between the focus and the directrix ___ in this case, midway between 2 and 4 in the y-direction

so the vertex is located at ___ (-4,3)