[tex]\left \{ {{x+2y=31} \atop {2y-x=29}} \right.\\\\\left \{ {{x=31-2y} \atop {2y-(31-2y)=29}} \right. \\\\\left \{ {{x=31-2y} \atop {2y-31+2y=29}} \right. \\\\\left \{ {{x=31-2y} \atop {4y=60}/:4} \right. \\\\\left \{ {{x=31-2y} \atop {y=15}} \right. \\\\\left \{ {{x=31-2*15} \atop {y=15}} \right. \\\\\left \{ {{x=31-30} \atop {y=15}} \right. \\\\\left \{ {{x=1} \atop {y=15}} \right.[/tex]
liczę na naj ;)
