Question 1120049
{{{(n-4)^2+(n-2)^2+n^2=371}}}

{{{(n^2-8n+16)+(n^2-4n+4)+n^2=371}}}

{{{3n^2-12n+20-371=0}}}

{{{3n^2-12n-351=0}}}

{{{n^2-4n-117=0}}}

{{{(n-13)(n+9)=0}}} n=13 or -9. The numbers are 9,11,13 or -13,-11,-9. Check:

{{{9^2+11^2+13^2=371}}}

{{{81+121+169=371}}}

{{{371=371}}}