Question 939802
{{{A(x+2)+B(2x+1)=3}}}
{{{Ax+2A+2Bx+B=3}}}
{{{(A+2B)x+(2A+B)=3}}}
So then,
{{{A+2B=0}}}
{{{2A+B=3}}}
From the first,
{{{A=-2B}}}
Substitute,
{{{2(-2B)+B=3}}}
{{{-4B+B=3}}}
{{{-3B=3}}}
{{{B=-1}}}
Then,
{{{A=-2(-1)}}}
{{{A=2}}}
So,
{{{A+B=2-1}}}
{{{highlight(A+B=1)}}}