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| Question 530268:  parabola,x^2 +6x -y +11 =0
 find the vertex,focus and directrix of the parabola
 Answer by lwsshak3(11628)
      (Show Source): 
You can put this solution on YOUR website! parabola,x^2 +6x -y +11 =0 find the vertex,focus and directrix of the parabola
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 Standard form of equation for parabola: (x-h)^2=4p(y-k), (h,k) being the (x,y) coordinates of the vertex.
 x^2 +6x -y +11 =0
 complete the square:
 y=(x^2+6x+9)+11-9
 y=(x+3)^2+2
 Rewrite in standard form
 (x+3)^2=(y-2)
 Vertex: (-3,2)
 4p=1
 p=1/4
 focus: (-3,9/4)
 directrix: y=7/4
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