-2(x+y)+5(2x+y)=124(y-x)+3(x-y)=-7
-2(x+y)+5(2x+y)=12
4(y-x)+3(x-y)=7
{-2x-2y+10x+5y=12
{4y-4x+3x-3y=7
{8x+3y=12
{y-x=7
{y=7+x
{8x+3(7+x)=12
{8x+3x=12-21
[11x=-9
{x=-9/11
{y=7+(-9/11)=6 ²/₁₁
-2x-2y+10x+5y=12
8x+3y=12
4y-4x+3x-3y=-7
y-x=-7
-2(x+y)+5(2x+y)=12
4(y-x)+3(x-y)=7
{-2x-2y+10x+5y=12
{4y-4x+3x-3y=7
{8x+3y=12
{y-x=7
{8x+3y=12
{y=7+x
{8x+3(7+x)=12
{y=7+x
{8x+3x=12-21
{y=7+x
[11x=-9
{y=7+x
{x=-9/11
{y=7+(-9/11)=6 ²/₁₁
{x=-9/11