Question 1199471
{{{system(p+n+d+q=30,p+5n+10d+25q=331,p+n-d-q=0,25q=5*10d)}}}


{{{system(p+n+d+q=30,p+5n+10d+25q=331,p+n-d-q=0,q=2d)}}}


E1 and E3 each have expression p+n.
{{{30-d-q=d+q}}}
{{{30=2(d+q)}}}
{{{d+q=15}}}



See this smaller system that can be found:
{{{system(q=2d,d+q=15)}}}


{{{d+2d=15}}}

{{{3d=15}}}

{{{highlight(d=5)}}}


Back to {{{q=2d}}},
{{{q=2*5}}}
{{{highlight(q=10)}}}

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