Matematika

Pertanyaan

tolong dibantu ya kak :) terima kasih yg udh mau bantu jawab
tolong dibantu ya kak :) terima kasih yg udh mau bantu jawab

2 Jawaban

  • x - y + 2z = -5
    x + y - z = 3
    ___________-
    -2y + 3z = -8

    2x + y + z = -1 |×1
    x + y - z = 3 |×2
    __________-

    2x + y + z = -1
    2x + 2y - 2z = 6
    _____________-
    -y + 3z = -7

    -2y + 3z = -8
    -y + 3z = -7
    __________-
    -y = -1
    y = 1

    -y + 3z = -7
    (subtitusikan nilai y)
    -(1) + 3z = -7
    -1 + 3z = -7
    3z = -7 + 1
    3z = -6
    z = -6/3
    z = -2

    x + y - z = 3
    (subtitusikan nilai y dan z)
    x + (1) -(-2) = 3
    x + 1 + 2 = 3
    x + 3 = 3
    x = 3 - 3
    x = 0

    jadi, x = 0 ; y = 1 ; dan z = -2


  • x-y+2z = -5 ...(1)
    2x+y+z = -1 ...(2)
    x+y-z = 3 ...(3)

    Eliminasi salah satu variabel
    x-y+2z = -5
    2x+y+z = -1
    __________+
    3x+3z =-6 ...(4)

    2x+y+z = -1
    x+y-z = 3
    __________-
    x+2z = -4 ...(5)

    3x+3z = -6
    x+2z = -4 ×3
    __________-
    3x+3z = -6
    3x+6z = -12
    __________-
    -3z = 6
    z = -2

    Substitusikan x ke...(5)
    x+2z = -4
    -2+2z = -4
    2z = -2
    z = -1

    Substitusikan x dan z ke ...(1)
    x-y+2z = -5
    -2-y+2(-1) = -5
    -y-4 = -5
    -y = -1
    y = 1

    Jadi, x = -2; y = 1; dan z = -1

    Semoga membantu dan bisa dipahami serta jawabannya tepat.