[tex]a*b=925=\ \textgreater \ b= \frac{925}{a} [/tex]
[tex](a+12)b=1225=\ \textgreater \ (a+12) \frac{925}{a} =1225[/tex]
[tex]=\ \textgreater \ 925(a+12)=1225a[/tex]
[tex]=\ \textgreater \ 925 (a+12)-1225 a=0[/tex]
[tex]=\ \textgreater \ 925 a-1225 a+11100=0[/tex]
[tex]=\ \textgreater \ -300a=-11100[/tex]
[tex]=\ \textgreater \ a=37[/tex]