Question 223764
Suppose a parabola has a vertx (-1,8) and y-intercept 7
How do you find the function f whose graph is this parabola and express f in the form f(x)= {{{ax^2+bx+c}}}?
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Vertex form: y-k = a(x-h)^2
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h=-1,k=8, y=7 when x = 0
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7-8 = a(0+1)^2
-1 = a
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Equation:
y-8 = -1(x+1)^2
y = -(x^2+2x+1)+8
f(x) = -x^2-2x+7
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{{{graph(400,400,-10,l0,-10,10,-x^2-2x+7)}}}
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Cheers,
Stan H.