Question 302654
Convert to vertex form by completing the square.
{{{g(x)=a(x-h)^2+k}}}
where (h,k) is the vertex. 
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{{{f(x)=3x^2+18x+8}}}
{{{f(x)=3(x^2+6x)+8}}}
{{{f(x)=3(x^2+6x+9)+8-27}}}
{{{f(x)=3(x+3)^2-19}}}
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(-3,-19)
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{{{ drawing(300,300,-5,5,-20,5,grid(1),circle(-3,-19,.2),green(line(-3,-20,-3,20)),graph( 300, 300, -5, 5, -20,5, 3x^2+18x+8)) }}}