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Write the equation of the parabola in vertex form with the following conditions:Vertex: (0,4)Directrix: y = 2

Write the equation of the parabola in vertex form with the following conditions:Vertex-example-1
User Raag Saluja
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1 Answer

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We are given the vertex of the parabola (0,4) and the directrix y=2. This is a parabola with its axis of symmetry parallel to the y-axis.

The standard form of the parabola is


\mleft(x-h\mright)^2=4p(y-k)

Where (h,k) is the vertex of the parabola and the directrix is given as

y = k - p

We can find the value of p:

p= k - y = 4 - 2 = 2

Substituting, we have the equation of the parabola:


\begin{gathered} (x-0)^2=4\cdot2(y-4) \\ x^2=8(y-4) \end{gathered}

The first choice is correct

User Parselmouth
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