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Find an equation of the parabola with vertex , − 5 − 5 and directrix = x − 12 .

User Rinu
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1 Answer

4 votes

Answer:


x=−y26+y3−136


Step-by-step explanation:


Given -


Vertex (−2,1)

Directrix x=1


The vertex is in the 2nd quadrant. The directrix is parallel to the y-axis. So, the parabola opens to the left. The vertex of the parabola is not the origin. Then its general form is -


(y−k)2=−4.a.(x−h)


Where -

h and k are the coordinates of the vertex.


h=−2)


k=1


a=1.5 half the distance between Directrix and vertex [= distance between focus and vertex]

Substitute these values in the equation


(y−1)2=−4.1.5.(x+2)

y2−2y+1=−6x−12

−6x−12=y2−2y+1

−6x=y2−2y+1+12

x=y2−6−2y−6+13−6


x=−y26+y3−136

User My Name Is GYAN
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