Matematika B - 2014. jesen, 9.

$x-y+2=0i2x-y+2=0x-y+2=0\; ~i~\; 2\; x-y+2=0$

$x-y+1=0ix+y=0x-y+1=0~i~x+y=0$

$2x-y+3=0i2x+y+3=02\; x-y+3=0\; ~\; i\; ~\; 2\; x+y+3=0$

$2x-y-1=0i2x-y-3=02\; x-y-1=0\; ~\; i\; ~\; 2\; x-y-3=0$