Question 943783

{{{7m + 12n = -1}}}
{{{5m -3n = 7}}}....all terms multiply by {{{4}}}
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{{{7m + 12n = -1}}}
{{{20m -12n = 28}}}
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{{{7m + 12n+20m -12n = -1+28}}}

{{{7m +20m  =27}}}

{{{27m  =27}}}

{{{highlight(m  =1)}}}

go to {{{7m + 12n = -1}}}, substitute {{{m= 1}}}

{{{7*1 + 12n = -1}}}

{{{7 + 12n = -1}}}

{{{12n = -1-7}}}

{{{12n = -8}}}

{{{n = -8/12}}}

{{{highlight(n = -2/3)}}}