Пошаговое объяснение:
x = 2 + yx = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=5x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-1x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2xx = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 8x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=3x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = - 1/3x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = - 1/3y = 2x - 5 y=-2/3-5=-17/3x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = - 1/3y = 2x - 5 y=-2/3-5=-17/35)y=2-4x 8x = 5 - 3y 8x-5-3(2-4x) 8x = 5 - 6 + 12xx = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = - 1/3y = 2x - 5 y=-2/3-5=-17/35)y=2-4x 8x = 5 - 3y 8x-5-3(2-4x) 8x = 5 - 6 + 12x4x 1 x=1/4 y=-2-4*1/4=2-1 6) 3x - 5y = 8 - 3y - 5y = 8 y=-1 x=1x = 2 + y3x - 2y = 9 3*(2+y)-2y=9 6 + 3y - 2y = 9 y=9-6 y=3 x=2+3=52) 5x+y=4 5*(3+2y)+y=4 15+10y+y=4 11y=-11 y=-1x = 3 + 2y x=3+2*(-1)=3-2-13) y = 11 - 2x5x - 4y = 8 5x - 4(11 - 2x) = 8 5x - 44 + 8x = 813x = 44 + 8 13x = 52 x = 4 y=11-2*4=11-8=34) x-2y=11 x-2(2x-5)=11 x-4x+10=11 3x = - 1x = - 1/3y = 2x - 5 y=-2/3-5=-17/35)y=2-4x 8x = 5 - 3y 8x-5-3(2-4x) 8x = 5 - 6 + 12x4x 1 x=1/4 y=-2-4*1/4=2-1 6) 3x - 5y = 8 - 3y - 5y = 8 y=-1 x=1x=-y
60*3=180 км - проехал 2 поезд
255-180= 75 км - между ними через 3 часа