SOLUTION: -1/16x2=y find the focus and directric of the parabola

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Question 197848: -1/16x2=y
find the focus and directric of the parabola
Found 2 solutions by stanbon, Mathtut:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
-1/16x2=y
find the focus and directrix of the parabola
x^2 = -16y
Form: (x-h)^2 = 4p(y-k)
Center: (0.0)
4p = -16
p = -4
---------------------
Opens downward.
-------
Focus: (h,k-p) ; (0,4)
Directrix: y = -4
=============================
Cheers,
Stan H.

Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
y=%28-1%2F16%29x%5E2
:
1/4p=-1/16
:
4p=-16
:
p=-4
:
focus is at (0,-4)
:
directrix is at y=4
:
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C%28-1%2F16%29x%5E2%29