a) y=-2x-1 x=y+7 y=-2(y+7) y=-2y-14 3y=-14 y=-14/3=-4 1/3 x=4 1/3+ 7=11 1/3 y=-4 1/3 x=11 1/3 b) -3x=2y y=1-x -3x=2(1-x) -3x=2-2x -x=2 x=-2 y=1-x y=1+2 y=3 x=-2 c) x+y=0 x-y=10 x=-y -y-y=10 -2y=10 y=-5 x+y=0 x-5=0 x=5 y=-5 d) 8x-6y=10 7x+y=5 y=5-7x 8x+6(5-7x)=10 8x+30-35x=10 -27x=-20 x=20/27 y=5-7(20/27) y=5-(5 5/27) y=5-140/27 y=-5/27 x=20/27 Pozdro, chyba się nie machnąłem nigdzie :)
a) y=-2x-1 x=y+7 y=-2*(y+7)-1 x=y+7 x=y+7 y=-2y-14-1 x=y+7 y+2y=-15 x=y+7 3y=-15/3 x=y+7 y=-5 y=-5 x=2 b)-3x=2y y=1-x y=1-x -3x=2*(1-x) y=1-x -3x=2-2x y=1-x -3x+2x=2 y=1-x -x=2/*(-1) x=-2 y=1-2=-1 c)x+y=0 x-y=10 x+y=0 x=10+y x=10+y 10+y+y=0 x=10+y 2y=10/2 y=5 x=10+5=15 d)8x-6y=10 7x+y=5 8x-6y=10 y=5-7x y=5-7x 8x-6*(5-7x)=10 y=5-7x 8x-30+42x=10 y=5-7x 50x=40/50 y=5-7x x=40/50 (w ułamku) x=40/50 y=5-7*40/50 x=40/50 y=5-280/50
a) y=-2x-1 x=y+7 y=2x-1 x=2x-1+7 y=2x-1 x-2x=-1+7 y=2x-1 -x=6 /:-1 y=2x-1 x=-6 y=2*(-6)-1 x=-6 y=-13 x=-6 b) -3x=2y y=1-x -3x=2(1-x) y=1-x -3x=2-2x y=1-x -3x+2x=2 y=1-x -x=2 /:-1 y=1-x x=-2 y=3 c) x+y=0 x-y=10 x=-y x-y=10 x=-y -y-y=10 x=-y -2y=10 /:-2 x=-y y=-5 x=5 y=-5 d) 8x-6y=10 /:2 7x+y=5 4x-3y=5 y=5-7x 4x-3(5-7x)=5 y=5-7x 4x-15+21x=5 y=5-7x 25x=20 /:25 y=5-7x x=0,8 y=5-7*0,8 x=0,8 y=0,6
