wyznacz niewiadome x i y z: 3x=12y 2x-y=10 x-5y= -17 3x+y=9 6x-3y=9 x+5y= -9,5 proszę pomocy :(

1) x =4y 2)y=-10+2x 3)x=-17+5y 4)y=9-3x 5)y=-3+2x 6)x=-9,5-5y liczę na naj :-)

3x=12y/:3 x=4y 3x=12y/:12 y=3/12x y=1/4x 2x-y=10 2x=10+y/:2 x=5+1/2y 2x-y=10 -y=10-2x/*(-1) y=2x-10 x-5y= -17  x=5y-17 x-5y=-17 -5y=-17-x/(-5) y=17/5+1/5 y=3 2/5+1/5 3x+y=9 y=9-3x 3x=9-y/:3 x=3-1/3y 6x-3y=9 6x=9+3y/:6 x=9/6+2y x=1 1/2+2y 6x-3y=9 -3y=9-6x/:(-3) y=-3+2x x+5y= -9,5 x=-9,5-5y x+5y=-9,5 5y=-9,5-x/:5 y=-1,9-0,2x