|
Question 1087425: Sketch the graph and identify focus, directrix, vertex, latus rectum and axis of symmetry: x^2 = 18y
Thank you very much!
Answer by Edwin McCravy(20056) (Show Source):
You can put this solution on YOUR website! This one is similar to the other ones I did for you except that
y and x are interchanged, h and k are interchanged, graphs opening
right and left are changed to opening up and down.
has vertex (h,k), and distance from vertex to both focus
and directrix is |p|. If p is positive the parabola opens
upward with the horizontal directrix is |p| units below the
vertex and the focus is |p| units above the vertex.
has vertex (0,0), and distance from vertex to both focus
and directrix is |18/4| or 9/2. Since 9/2 is positive the
parabola opens upward with the vertical directrix 9/2 units
below the vertex and the focus is 9/2 above the vertex.
So the focus is 9/2 units above vertex (0,0) which is (0,9/2),
and the directrix is a horizontal line 9/2 units below the
vertex (0,0) which is the horizontal line y = -9/2
Edwin
|
|
|
| |