Question 855009
the vertex is (3,5) and finally the y-intercept = (0,8) I only got that no equation how to I graph that? 
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Plot those points.
Sketch a parabola opening upward from (3,5) and passing thru (0,8)
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By symetry along x = 3, the parabola also passes thru (6,8)
Form: y = ax^2 + bx + c
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Equations:
Using (0,8) you get:: 0  +  0  +  c  = 8
Using (6,8) you get:: 36a+ 6b  +  c  = 8
Using (3,5) you get:: 9a + 3b  +  c =  5
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Solve the system to get:
a = 1/3
b = -2
c = 8
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Equation:
y = (1/3)x^2 - 2x + 8
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{{{graph(400,400,-10,10,-10,10,(1/3)x^2 - 2x + 8)}}}
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Cheers,
Stan H.
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