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May 7th, 2010, 03:41 PM   #1
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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 = -2x-10

y^2 + 4y + 4 = -2x-6

(y+2)^2= -2(x+3)



vertex: (-3, -2)

Focus: (-3.5, -2)

Directrix: -2.5
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May 7th, 2010, 09:37 PM   #2
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Re: Identify the vertex, focus and the directrix

Perfect.
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May 18th, 2010, 04:19 PM   #3
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Re: Identify the vertex, focus and the directrix

Quote:
Originally Posted by The Chaz
Perfect.
In subtlety, maybe.
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