Question 981430
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{{{ graph( 800, 800, -15, 15, -15, 15, 3x^2-12x-3) }}}
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Standard form: {{{y=ax^2-bx+c}}}
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y=3x^2-12x-3
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x value of vertex: 
{{{x=-b/2a}}}
{{{x=-(-12)/((2)(3))}}}
{{{x=12/6}}}
{{{x=2}}}
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Use the x value in original equation to get y value.
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{{{y=3x^2-12x-3}}}
{{{y=3(2^2)-12(2)-3}}}
{{{y=12-24-3}}}
{{{y=-15}}}
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The vertex is (2,-15)