Question 123243
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Discussion
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The vertex of any parabola in the form {{{y=f(x)=ax^2+bx+c}}} is at the point
({{{-b/2a}}},{{{f(-b/2a)}}}) 
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Solution
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For {{{y=f(x)=x^2-2x-3}}}

{{{a=1}}}
{{{b=-2}}}


{{{-b/2a=(-(-2))/(2*1)=2/2=1}}}
{{{f(1)=(1)^2-2(1)-3=1-2-3=-4}}}


The vertex is at (1,-4)
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Check Answer
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{{{graph(600,600,-5,5,-5,5,x^2-2x-3)}}}

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