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May 7th, 2010, 03:41 PM  #1 
Member Joined: Sep 2009 Posts: 43 Thanks: 0  Identify the vertex, focus and the directrix
Sketech the graph of the equation y^2+4y+2x+10=0. Identify the vertex, the focus and the equation for the directrix. Use the completing the square to put the equation into standard form as your first step. This is what I did. y^2 + 4y = 2x10 y^2 + 4y + 4 = 2x6 (y+2)^2= 2(x+3) vertex: (3, 2) Focus: (3.5, 2) Directrix: 2.5 
May 7th, 2010, 09:37 PM  #2 
Global Moderator Joined: Nov 2009 From: Northwest Arkansas Posts: 2,767 Thanks: 5  Re: Identify the vertex, focus and the directrix
Perfect.

May 18th, 2010, 04:19 PM  #3  
Senior Member Joined: Jan 2009 Posts: 345 Thanks: 3  Re: Identify the vertex, focus and the directrix Quote:
 

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