Question 829886
1.{{{A+B=11}}}
2.{{{A*B=30}}}
Multiply eq. 1 by A,
{{{A^2+AB=11A}}}
Substitute from eq. 2, 
{{{A^2+30=11A}}}
{{{A^2-11A+30=0}}}
{{{(A-5)(A-6)=0}}}
Two solution: {{{A=5}}}, then {{{B=6}}} or {{{A=6}}} then {{{B=5}}}.