{ x/4 + y/4 = 2 x/6 - 2 = -y/3 x + y = 8 - mnożymy przez - 1 x - 12 = - 2 -x - y = -8 x - 12 = -2 dodajemy -y - 12 = - 10 -y = -10 + 12 -y = 2 y = -2 x + y = 8 x - 2 = 8 x = 8 + 2 = 10 x = 10 y = -2 x + y = 8 x - 2 = 8 x = 8 + 2 x = 10 odp x = 10 , y = -2 zad 2 { x+y/2 - 2y/3 = 5/2 3x/2 + 2y = 0 3x + 6 - 4y = 15 3x + 4y = 0 3x - 4y = 9 3x + 4y = 0 dodajemy 6x = 9 x = 9/6 = 3/2 3x + 4y = 0 9/2 + 4y = 0 4y = 9/2 y = 9/8 odp x = 3/2 y = 9/8
a) { x/4 + y/4 = 2 |*4 x/6 - 2 = -y/3 |*6 x+y=8 x-12=2y |*(-1) x+y=8 -x+12=-2y x+y=8 -x+2y=-12 _________________________________ x+y-x+2y=8-12 3y=-4 |:3 y=4/3 y=1 i 1/3 x+y=8 x=8-y x=8-1 i 1/3 x=6 i 2/3 {y=1i1/3 x=6i 2/3 b) { x+y/2 - 2y/3 = 5/2 |*6 3x/2 + 2y = 0 |*(-4) 6x+3y-4y=15 -6x-8y=0 6x-y=15 -6x-8y=0 __________________________________ 6x-y-6x-8y=15 9y=15 |:9 y=15/9 y=1i 2/3 6x-y=15 6x=15+y 6x=15+1i 2/3 6x=16i 2/3 |:6 16i 2/3 x= _________ 6 {y=1i 2/3 16i 2/3 x= _________ 6