x + 3y = 18 -X – 4y = -25

Question

x + 3y = 18
-X – 4y = -25

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King 5 years 2021-07-26T05:45:26+00:00 2 Answers 12 views 0

Answers ( )

  1. diemkieu
    0
    2021-07-26T05:46:56+00:00
    Reply

    Answer:

    x = -3

    y= 7

    Step-by-step explanation:

    x + 3y=18 —-(1)

    -x – 4y=-25 —–(2)

    from equation (1)

    x = 18 – 3y —(3)

    putting equation (3) into equation (2)

    -(18 – 3y) – 4y = -25

    18 + 3y -4y = -25

    3y – 4y = -25 – 18

    -y = -7

    y = 7 ✓

    Putting y=7 into equation (1)

    x + 3(7) = 18

    x + 21 = 18

    x = 18 – 21

    x = -3 ✓

  2. giabao
    0
    2021-07-26T05:47:17+00:00
    Reply

    -y=-7
    Y=7
    -x-4(-7)=-25
    -x+28=-25
    -x=3
    X=-3

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