Question 1084896
{{{y=a(x-h)^2+k}}} would have vertex at  (h, k).



{{{a(x-h)^2+k=y}}}
{{{a(x-h)^2=y-k}}}
{{{a=(y-k)/(x-h)^2}}}, a symbolic solution for factor, a.


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Using given vertex and other point on the graph,

{{{a=(8-4)/(4-(-1))^2}}}

{{{a=4/(5)^2}}}

{{{a=4/25}}}

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{{{highlight(y=(4/25)(x+1)^2+4)}}}