Regan is trying to find the equation of a quadratic that has a focus of (−2, 5) and a directrix of y = 13. Describe to Regan your preferred method for deriving the equation. Make sure you use Regan's situation as a model to help her understand.

Question

anonymous · Answer

@phi

phi · Answer

a quadratic is a parabola
You should first find the vertex, which is halfway between the focus and the directrix
what do you get ?

anonymous · Answer

√(x2--2)^2+(y1-5)^2=  √(y2-13)^2

phi · Answer

what is the vertex ?

anonymous · Answer

I get this when I simplify it but I don't know the vertex...

X^2+(y1-5)^2+2=y2-13

phi · Answer

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