Question 145532
x^2-6x+8=y
x^2-6x+8=0 when y=0 you have the x intercepts.
(x-4)(x-2)=0
x=4, x=2 the x intercepts
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x^2-6x+8=y
y=8 when x=0 The y intercept.
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The axis of symmetry is a vertical line 1/2 way between the x intercepts.
x=3 This is also the x-coordinate of the vertex.
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The y coordinate of the vertex is -(b^2-4ac)/4a=-(36-(4*1*8))/(4*1)=-(36-32)/4=-4/4=-1
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Ed
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Check these numbers with the graph to understand what they mean.
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{{{graph(500,500,-10,10,-10,10,x^2-6x+8)}}}