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    A parabola has a vertex with co-ordinates (-4,1) and goes through the point (2,-17)

    Find the equation of the parabola in the form y= ax^2 + bx +c


    I've used the vertex to get y=(x+4)^2+1

    But I'm not sure what to do next.
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    What you should have got is actually y=a(x+4)^2+1 rather than y=(x+4)^2+1. You need to find the value of a.
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    Sorry for my stupidity, but how do I find A?
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    (Original post by stayd001)
    Sorry for my stupidity, but how do I find A?
    Expand out your expression and remember that the point (2, -17) is on the parabola.
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    (Original post by stayd001)
    Sorry for my stupidity, but how do I find A?
    sub in the values you were given for passing through a point
 
 
 
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Updated: September 28, 2010
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