A {x=3-2y {2*(3-2y)+y=12 {x=3-2y {6-4y+y=12 {x=3-2y {-3y=6 /:(-3) {x=3-2y {y=-2 {x=3-2*(-2) {y=-2 {x=3+4 {y=-2 {x=7 B {x+2y=3 {y=12-2x {x+2*(12-2x)=3 {y=12-2x {x+24-4x=3 {y=12-2x -3x=-21 /:(-3) {y=12-2x {x=7 {y=12-2*7 {x=7 {y=12-14 {x=7 {y=-2 Licze na naj...
x+2y=3 2x+y=12 x=3-2y 2(3-2y)+y=12 x=3-2y 6-4y+y=12 x=3-2y -3y=12-6 x=3-2y -3y=6 x=3-2y y=6:(-3) x=3-2y y=-2 x=3-2×(-2) y=-2 x=3+4 y=-2 x=7 y=-2 x+2y=3 2x+y=12 x+2y=3 y=12-2x x+2(12-2x)=3 y=12-2x x+24-4x=3 y=12-2x -3x=3-24 y=12-2x -3x=-21 y=12-2x x=-21:-3 y=12-2x x=7 y=12-2×7 x=7 y=12-14 x=7 y=-2
a) x+2y=3 2x+y=12 x=3-2y 2(3-2y)+y=12 6-4y+y=12 6-3y=12 -3y=6 y=-2 x=3-2*(-2) x=7 x=7 y=-2 b) x+2y=3 2x+y=12 y=12-2x x+2(12-2x)=3 x+24-4x=3 -3x=-21 x=7 y=12-2*7 y=-2 x=7 y=-2