Question 1146078
{{{system(y+x=62,y-7=3(x-7))}}}


{{{y-7=3(62-y-7)}}}
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{{{y-7=3(55-y)}}}
{{{y-7=3*55-3y}}}
{{{4y-7=3*55}}}
{{{4y=3*55+7}}}
{{{4y=172}}}
{{{highlight(y=43)}}}