SOLUTION: The vertex of parabola is at the point (-1, -3). how do i get the equation of the parabola?

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Question 144766: The vertex of parabola is at the point (-1, -3). how do i get the equation of the parabola?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The vertex of parabola is at the point (-1, -3). how do i get the equation of the parabola?
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Form y = ax^2 + bx + c
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The vertex occurs where x = -b/2a
So, -b/2a = -1 ; b = 2a
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Therefore, let a = 1,then b = 2
y = x^2 + 2x + c
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But y = -3 when x = -1,so:
-3 = 1 -2 + c
c = -2
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EQUATION:
y = x^2 + 2x -2 is a parabola with vertex = (-1,-3).
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Cheers,
Stan H.
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