Question 341469
In vertex form,
{{{y=a(x-h)^2+k}}}
{{{y=a(x-(-4))^2+5}}}
{{{y=a(x+4)^2+5}}}
When {{{x=0}}}
{{{16a+5=-27}}}
{{{16a=-32}}}
{{{a=-2}}}
.
.
.
{{{y=-2(x+4)^2+5=0}}}
{{{2(x+4)^2=5}}}
{{{(x+4)^2=5/2}}}
{{{x+4=0 +- sqrt(5/2)}}}
{{{highlight(x=-4 +- sqrt(10)/2)}}}
.
.
.
{{{drawing(300,300,-8,2,-4,6,circle(-4,5,0.2),circle(-4+sqrt(10)/2,0,0.2),
circle(-4-sqrt(10)/2,0,0.2),graph(300,300,-8,2,-4,6,-2(x+4)^2+5))}}}