a ) 4y - x = 6 17 y = 0 4y=6+x /:4 y=1,5+1/4x 17*(1,5+1/4x)=0 25,5+4,25x=0 4,25x=-25,5 /:4,25 x=-6 4y-(-6)=6 4y+6=6 4y=6-6 4y=0 /:4 y=0 b ) u = 4v 5u -v = 10 5*4v-v=10 20v-v=10 19v=10 /19 v=10/19 u=4*10/19 u=40/19 u=2 2/19 c ) x+ 3y =3 x-y=5 x=3-3y 3-3y-y=5 3-2y=5 -2y=5-3 -2y=2 /:-2 y=-1 x=3-3*(-1) x=3-(-3) x=3+3 x=6 d ) 2x - y = 10 x+5y = -17 x=-17-5y 2*(-17-5y)-y=10 -34-10y-y=10 -11y=10+34 -11y=44 /:-11 y=-4 x=-17-5*-4 x=-17-(-20) x=-17+20 x=3
a ) 4y - x = 6 17 y = 0 4y - x = 6 y = 0 -x=6 y=0 x=-6 y=0 b ) u = 4v 5u -v = 10 5*4v-v=10 20v-v=10 19v=10 v=10/19 u=4*10/19 u=40/19 c ) x+ 3y =3 x-y=5 x=3-3y 3-3y-y=5 3-4y=5 -4y=5-3 -4y=2 y=-1/2 x=3-3*(-1/2) x=3+3/2 x=4i1/2 d ) 2x - y = 10 x+5y = -17 -y=10-2x y=2x-10 x+5*(2x-10)=-17 x+10x-50=-17 11x=-17+50 11x=33 x=3 y=2*3-10 y=6-10 y=-4
