e) / 4x-2y=6 3x-6y=12 /:3 4x - 2y = 6 x - 2y = 4 4x - 2y = 6 x = 4 + 2y 4(4 + 2y) - 2y = 6 x = 4 + 2y 16 + 8y - 2y = 6 x = 4 + 2y 6y = 6 - 16 x = 4 + 2y 6y = -10/:6 x = 4 + 2y y = - 5/3 x = 4 + 2(-5/3) y = -5/3 x = 4 - 3 1/3 y = -5/3 x = 2/3 f) /3x-4y=14 -2x+7y=-18/:(-2) 3x - 4y = 14 x - 3,5y = 9 3x - 4y = 14 x = 9 + 3,5y 3(9 + 3,5y) b- 4y = 14 x = 9 + 3,5y 27 + 10,5y - 4y = 15 x = 9 + 3,5y 6,5y = -13/: 6,5 x = 9 + 3,5y y = - 2 x = 9 + 3,5*(-2) y = -2 y = 9 - 7 y = - 2 x = 2 3/82 e) / 2x+y=14 /:2 5x+4y=17 x + 0,5y = 7 5x + 4y = 17 x = 7 - 0,5y 5 * (7 - 0,5y) + 4v = 17 x = 7 - 0,5y 35 - 2,5y + y = 17 x = 7 - 0,5y -1,5y = 17 - 35 x = 7 - 0,5y - 1,5y = - 18 /: (-1,5 x = 7 - 0,5y y = 12 x = 7 - 0,5*12 y = 12 x = 7 - 6 y = 15 x = 1 y = 15
e) 4x-2y=6|:2 3x-6y=12 2x-y=3 3x-6y=12 -y=3-2x|:(-1) 3x-6y=12 y=-3+2x 3x-6(-3+2x)=12 3x+18-12x=12 -9x=9 x=-1 y=-3+2(-1) y=-3-2 y=-5 f) x-4y=14 -2x+7y=-18 x=14+4y -2(14+4y)+7y=-18 -28-8y+7y=-18 -y=10 y=-1 x=14+4(-1) x=14-4 x=10 3/82 e) 2x+y=14 5x+4y=17 y=14-2x 5x+4(14-2x)=17 5x+56-8x=17 -3x=-39 x=13 y=14-2*13 y=14-26 y=-12
