SOLUTION: Derive the equation of the parabola with a focus at (−5, 5) and a directrix of y = -1.

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Question 934767: Derive the equation of the parabola with a focus at (−5, 5) and a directrix of y = -1.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Use the distance formula and the definition of parabola. You want the set of points equally distant from (-5,5) as from (x,-1).



sqrt%28%28x%2B5%29%5E2%2B%28y-5%29%5E2%29=sqrt%28%28y%2B1%29%5E2%29

%28x%2B5%29%5E2%2B%28y-5%29%5E2=%28y%2B1%29%5E2

Continue simplifying until you have an equation formula of y in terms of x.