Question 950705
{{{(3+2S)^2=(7+S)^2+S^2}}}
{{{4S^2+12S+9=S^2+14S+49+S^2}}}
{{{4S^2+12S+9=2S^2+14S+49}}}
{{{2S^2-2S-40=0}}}
{{{S^2-S-20=0}}}
{{{(S-5)(S+4)=0}}}
Only the positive solution makes sense here.
{{{S-5=0}}}
{{{S=5}}}
So then,
{{{3+2S=3+2(5)=3+10=13}}}
{{{7+S=7+5=12}}}
7-12-13 triangle