SOLUTION: Please show me the steps to solve this for the vertex, axis of symmetry, focus and directrix: y-4=-1/16(x+1)^2

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Question 857001: Please show me the steps to solve this for the vertex, axis of symmetry, focus and directrix:
y-4=-1/16(x+1)^2

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
solve this for the vertex, axis of symmetry, focus and directrix:
y-4=-1/16(x+1)^2
(x+1)^2=-16(y-4)
This is an equation of a parabola that opens down.
Its basic form of equation: (x-h)^2=4p(y-k), (h,k)=coordinates of the vertex
For given parabola:
vertex: (-1,4)
axis of symmetry: x=-1
4p=16
p=4
focus: (-1,0) (p-distance below vertex on the axis of symmetry)
directrix: y=8 (p-distance above vertex on the axis of symmetry)