Q. Write the equation in vertex form for the parabola with vertex (0,−2) and directrix y=−9.Simplify any fractions.______
Vertex and Directrix Information: Vertex: (0,−2)Directrix: y=−9Since the directrix is horizontal, the parabola is vertical.
Vertex Form of Parabola: Vertex form of a vertical parabola: y=a(x−h)2+k
Direction of Parabola: The vertex is above the directrix, so the parabola opens upwards.
Distance Calculation: Distance between vertex and directrix: ∣−2−(−9)∣=7
Calculation of 'a': The value of a is 4p1, where p is the distance from the vertex to the focus (which is the same as the distance to the directrix).a=4×71a=281
Substitution into Vertex Form: Substitute a=281, h=0, and k=−2 into the vertex form equation.y=281(x−0)2−2y=281x2−2
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