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The focus of a parabola is (0,−2) . The directrix of the parabola is y=-1 .

 Mar 15, 2019
 #1
avatar+99237 
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I assume you need the equation for the parabola

 

The vertex  lies at   (0, - 1.5)

Since the directrix is above the focus....the parabola turns downward

p =   l  -1 - - 1.5 l  = l .5 l  =     =   .5

 

So...we have this form

 

4p ( y + 1.5) =  - ( x - 0)^2

 

4(.5)(y + 1.5) = - x^2

 

2 ( y + 1.5) = -x^2

 

y + 1.5 =  -(1/2)x^2

 

y =   -(1/2) x^2 - 1.5

 

Here's the graph :  https://www.desmos.com/calculator/kqbcr8utzm

 

cool cool cool

 Mar 15, 2019

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