Raczej metoda podstawiania.
[tex]\left \{ {{x-y=-4} \atop {3x+2y=23}} \right. \\\left \{ {{x=-4+y} \atop {3(-4+y)+2y=23}} \right. \\\left \{ {{x=-4+y} \atop {-12+3y+2y=23}} \right. \\\left \{ {{x=-4+y} \atop {5y=23+12}} \right. \\\left \{ {{x=-4+y} \atop {5y=35/:5}} \right. \\\left \{ {{x=-4+y} \atop {y=7}} \right. \\\left \{ {{x=-4+7} \atop {y=7}} \right. \\\left \{ {{x=3} \atop {y=7}} \right.[/tex]
Metoda przeciwnych wspolczynnikow
[tex]\left \{ {{x-y=-4 /*2} \atop {3x+2y=23}} \right. \\+\left \{ {{2x-2y=-8} \atop {3x+2y=23}}\right. \\2x+3x=-8+23\\5x=15 /:5\\x=3\\x-y=-4\\3-y=-4 /-3\\-y=-7\\y=7[/tex]
