a) 5p-2r=21 / *3 3p+5r=-6 /*(-5) 15p-6r=63 -15p-25r=30 ____________ -31r=93/ /(-31) r=-3 5p-2r=21 /*5 3p+5r=-6 /*2 25p-10r=105 6p+10r= -12 ____________ 31p= 93/ /31 p=3 r=-3 b) 2x - 3y = 10 /*5 5x + 5y = 0 /*(-2) 10x-15y=50 -10x-10y=0 ____________ -25y=50/ /(-25) y=-2 2x - 3y = 10 /*5 5x + 5y = 0 /*3 10x-15y=50 15x+15y=0 ____________ 25x=50 / /25 x=2 y=-2 c) 4x + 5y = 12,3 /*3 3x - 2y = -4 /*(-4) 12x+15y=36,9 -12x+8y=16 ___________ 23y=52,9 //23 y=2,3 4x + 5y = 12,3 /*2 3x - 2y = -4 /*5 8x+10y=24,6 15x-10y=-20 _____________ 23x= 4,6 / /23 x=0,3 y=2,3
a) 5p - 2r = 21//*(-3) 3p + 5r = -6//*(5) -15p +6r = - 63 15p +25=-30 31r=-33/:31 r= - 33/31 5p- 2 *(- 33/31)= 21 5p +66/31=21 5p=21-66/31 5p=585/31//:5 p=117/31 b) 2x - 3y = 10//*(-5) 5x + 5y = 0//*2 -10x + 15y = - 50 10x +10y= 0 25y=-50//25 y=-2 2x - 3*(-2)=10 2x+6=10 2x=10-6 2x=4//:2 x=2 c) 4x + 5y = 12,3//*2 3x - 2y = -4 //*5 8x +10y = 24,6 15x - 10y = - 20 23x=-4,6/:23 x=- 0,2 3*(-0,2) - 2y=-4 - 0,6- 2y=-4 -2y=-4+0,6 -2y=-3,4//:(-2) y=1,7
a)5p - 2r=21 razy 3 3p + 5r= -6 razy -5 15p - 6r=63 -15p - 25r=30 -33r=99 podzielić na (-33) r= -3 3p+5r=-6 r=-3 3p-15=-6 dodać 15 3p=9 podzielić na 3 p=3 b) 2x-3y=10 razy 5 5x+5y=0 razy -2 10x-15y=50 -10x-10y=0 -25y=50 podzielić(-25) y= -2 y=-2 5x+5y=0 y=-2 5x-10=0 dodać 10 y=-2 5x=10 podzielić na 5 y=-2 x=2 c) 4x+5y=12.3 razy 2 3x-2y=-4 rzay 5 8x+10y=24.6 15x-10y=-20 23x=4.6 podzielić na 23 x=0.2 3x-2y=-4 x=0.2 0.6-2y=-4 odjąc 0.6 x=0.2 -2y=-4.6 podzielić na( -2) x=0.2 y=2.3
