SOLUTION: vertex= (0,4) directrix=y=-1 parabola opens up what is the directrix equation and the vertex equation?

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Question 1172023: vertex= (0,4) directrix=y=-1
parabola opens up
what is the directrix equation and the vertex equation?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
distance from vertex and either focus or directrix is 5 units. Equation of the parabola may have a factor, 4%2A5=20.

20%28y-4%29=x%5E2-----------this would be one of the equations you want.


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20%28y-4%29=%28x-0%29%5E2, a longer way to write the basic equation.