SOLUTION: 1) Write an equation of a parabola with a vertex at the origin and a focus at (-2,0)?

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Question 454198: 1) Write an equation of a parabola with a vertex at the origin and a focus at (-2,0)?
Answer by lwsshak3(11628) About Me  (Show Source):
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1) Write an equation of a parabola with a vertex at the origin and a focus at (-2,0)?
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Standard form of parabola: (y-k)^2=-4p(x-h), with (h,k) being the (x,y) coordinates of the vertex. This parabola opens leftwards and has a horizontal axis of symmetry.
For given problem:
Axis of symmetry = x-axis or y=0
p=distance from vertex to focus on axis of symmetry=2
center (0, 0)
Equation:
y^2=-8x
See graph below as a visual check on the equation
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y=(-8x)^.5
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%28-8x%29%5E.5%2C-%28-8x%29%5E.5%29+