Question 948107
A parabola has the vertex (2, -30 ) and passes through the point (5, -12 ). Find a function f with this graph.
 f(x) = 
Please explain how I would find the solution 
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Vertex form::
a(x-h)^2 = y-k
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Solve for "a"::
a(x-2)^2 = y+30
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a(5-2)^2 = -12+30
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9a = 18
a = 2
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Equation:
2(x-2)^2 = y+30
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y = 2(x-2)^2 -30
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y = 2x^2 - 8x -26
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{{{graph(400,400,-50,50,-50,50,2x^2-8x-26)}}}
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Cheers,
Stan H.
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