Question 1100797
Get the parabola into focus form by completing the square,
{{{x^2+6x+5=4y}}}
{{{(x^2+6x+9)+5=4y+9}}}
{{{(x+3)^2=4y+4}}}
{{{(x+3)^2=4(y+1)}}}
Compared to the focus form,
{{{(x-h)^2=4p(y-k)}}}
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(-3,-1) is the vertex.
{{{4p=4}}}
{{{p=1}}}
So the focus is (-3,-1)+(0,1)=(-3,0).
The directrix is then,
{{{y=-2}}}
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*[illustration des36.JPG].