Question 391557
{{{m+2n=1}}}
{{{5m+3n=-23}}}
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{{{m+2n=1}}}
{{{m=1-2n}}}
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{{{5m+3n=-2}}}
{{{5(1-2n)+3n=-2}}}
{{{5-10n+3n=-2}}}
{{{-7n=-7}}}
{{{n=1}}}
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{{{m+2n=1}}}
{{{m+2(1)=1}}}
{{{m=-1}}}