Find the equation of the parabola that satisfies the following conditi – InterviewSolution

1.	Find the equation of the parabola that satisfies the following conditions: Focus (0, –3); directrix y = 3
Answer» Focus = (0, –3); directrix y = 3 Since the focus lies on the y-axis, the y-axis is the axis of the parabola. Therefore, the equation of the parabola is either of the form x² = 4ay or x² = – 4ay. It is also seen that the directrix, y = 3 is above the x-axis, while the focus (0, –3) is below the x-axis. Hence, the parabola is of the form x2 = –4ay. Here, a = 3 Thus, the equation of the parabola is x² = –12y.

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