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26 August, 14:19

Solve by using elimination 7) - 6x - 8y = - 30

4x + 2y = 20

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Answers (1)
  1. 26 August, 16:08
    0
    x = 5, y = 0

    Step-by-step explanation by elimination:

    Solve the following system:

    {-6 x - 8 y = - 30 | (equation 1)

    4 x + 2 y = 20 | (equation 2)

    Add 2/3 * (equation 1) to equation 2:

    { - (6 x) - 8 y = - 30 | (equation 1)

    0 x - (10 y) / 3 = 0 | (equation 2)

    Divide equation 1 by - 2:

    {3 x + 4 y = 15 | (equation 1)

    0 x - (10 y) / 3 = 0 | (equation 2)

    Multiply equation 2 by 3/10:

    {3 x + 4 y = 15 | (equation 1)

    0 x - y = 0 | (equation 2)

    Multiply equation 2 by - 1:

    {3 x + 4 y = 15 | (equation 1)

    0 x+y = 0 | (equation 2)

    Subtract 4 * (equation 2) from equation 1:

    {3 x+0 y = 15 | (equation 1)

    0 x+y = 0 | (equation 2)

    Divide equation 1 by 3:

    {x+0 y = 5 | (equation 1)

    0 x+y = 0 | (equation 2)

    Collect results:

    Answer: {x = 5, y = 0
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