SOLUTION: Focus at (0, -5), directrix y = 5.

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Question 1191210: Focus at (0, -5), directrix y = 5.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Opens downward, vertex being a maximum point. If you know the formula for the equation to plug in the values given, then that is one option. Otherwise you can use the Distance Formula definition for a parabola.

%28x-0%29%5E2%2B%28y-%28-5%29%29%5E2=%28x-x%29%5E2%2B%28y-5%29%5E2
x%5E2%2B%28y%2B5%29%5E2=%28y-5%29%5E2
x%5E2%2By%5E2%2B10y%2B25=y%5E2-10y%2B25
x%5E2%2B10y=-10y
highlight%28x%5E2=-20y%29

graph%28400%2C400%2C-7%2C7%2C-7%2C7%2C-x%5E2%2F20%29