Problem 23 of 7
Derive the vertical parabola equation from focus (0,-3) and directrix y=-1.
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set distance to focus equal to distance to directrix.
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Focus and directrix must produce a vertical parabola with horizontal directrix.
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Your answer is equivalent to the expected form.
Walkthrough
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1. Find the vertex midway between focus and directrix.
2. Find p as directed distance from vertex to focus.
3. Substitute into (x-h)^2=4p(y-k).
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Wrong sign for p relative to opening direction.