Question 599369
What would the focus and directrix of the equation y=3x^2 -5x^2 +3?
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Form: (x-h)^2 = 4p(y-k)
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Your Problem:
y = -2x^2+3
y-3 = -2(x-0)^2
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4p = -2
p = -1/2
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Vertex: (0,3)
The parabola opens down so focus is at: (0,3-(1/2) = (0,5/2)
Directrix is y = 3-(-1/2) = 7/2
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{{{graph(400,400,-10,10,-10,10,-2x^2+3)}}}
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Cheers,
Stan H.
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