Question 892930
{{{A^2+B^2=256}}}
{{{(A+B)^2=784}}}
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{{{(A+B)^2=A^2+2AB+B^2}}}
{{{2AB=(A+B)^2-(A^2+B^2)}}}
{{{AB=(1/2)((A+B)^2-(A^2+B^2))}}}
{{{AB=(1/2)(784-256)}}}
{{{AB=(1/2)(528)}}}
{{{highlight(AB=264)}}}