a+b=m+n=25a-m=n-b2a+3b=2m+3n+102a-2m=3n-3b+102(a-m)=3(n-b)+102(a-m)-3(a-m)=10-(a-m)=10m-a=10
2a+3b=2(a+b)+b=50+b=2m+3n+10=2(m+n)+n+10=50+n+10b-n=m-a=10
