Question 552790: the focus of a parabola is (4, -3) and the directrix is y=6
write the equation of the parabola and then draw the graph. Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! the focus of a parabola is (4, -3) and the directrix is y=6
write the equation of the parabola and then draw the graph
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Equation is that of a parabola which opens downward. Its standard form: (x-h)^2=-4p(y-k), with (h,k) being the (x,y) coordinates of the vertex.
For given equation:
axis of symmetry: x=4
p=half the distance between the directrix and y-coordinate of the focus on the axis of symmetry.
p=(6+3)/2=9/2=4.5
vertex: (4, 3/2)
Equation of parabola:
y=(x-4)^2/-18+3/2
see graph below
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