Question 343421
Use the vertex form,
{{{y=a(x-12)^2-8}}}
Then use either point to solve for a.
{{{0=a(10-12)^2-8}}}
{{{a(-2)^2=8}}}
{{{a=8/4}}}
{{{a=2}}}
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{{{highlight(y=2(x-12)^2-8)}}}