Metoda przeciwnych współczynników {2x-y=4 { 5x-7y=3 {5x-7y=3 {2x-3y=7

2x-y=4 /*(-7) 5x-7y=3 -14x+7y=-28 5x-7y=3 -------------- dodaj 9x=-25 x=-25/9 x=-2 7/9 2x-y=4 2x-4=y 2*(-2 7/9)-4=y y=-86/9 y=-9 5/9 -------------------- {5x-7y=3 /*2 {2x-3y=7 /*(-5) 10x-14y=6 -10x+15y=-35 ---------------- dodajemy y=-29 2x-3y=7 2x=7+3y x=7/2+3/2y x=7/2+3/2*(-29) x=-40