SOLUTION: equation of parabola with focus (3,0) and directrix x+5=0

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Question 953622: equation of parabola with focus (3,0) and directrix x+5=0
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Follow the definition OF A PARABOLA and use the Distance Formula.
The directrix is same as x=-5, no restriction on y, for general points (-5,y).

sqrt%28%28x-3%29%5E2%2B%28y-0%29%5E2%29=sqrt%28%28x-%28-5%29%29%5E2%2B%28y-y%29%5E2%29
Simplify that and put into the form desired.

The parabola is the set of points equally distant from a point and a line. The left member shows distance from (x,y) to given point, the focus, (3,0); and the right member shows the distance from (x,y) to the given directrix x=-5. Those two distances must be equal for a parabola.