Question 301421
Complete the square to put it into vertex form.
{{{f(x)=x^2+8x+16-16}}}
{{{f(x)=(x+4)^2-16}}}
X coordinate of the vertex: {{{x=-4}}}
Y coordinate of the vertex: {{{y=-16}}}
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{{{drawing(300,300,-12,4,-20,20,circle(-4,-16,.25),green(line(-4,-30,-4,30)), graph( 300, 300, -12, 4, -20, 20, x^2+8x)) }}}