Rozwiaz uklad rownan liniowych metoda podstawiania   [latex]left { {{7x+8y=9} atop {5x+6y=2}} ight [/latex]

7x=9-8y 5x+6y=2   x=(9-8y)/7 5*(9-8y)/7+6y=2   x=(9-8y)/7 (45-40y)/7+6y=2   x=(9-8y)/7 45/7- 5 i 5/7y +6y=2   x=(9-8y)/7 2/7y=-4 i 5/7   x=(9-8y)/7 2/7y=-31/7   x=(9-8y)/7 2y=-31   x=(9-8y)/7 y=-15.5   x=(9-8*(-15.5))/7 y=-15.5   x=(9+124)/7 y=-15,5   x=19 y=-15,5