Algebra 8th grade

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3a + 5b = 70
6a + 9b = 135

  • Algebra 8th grade -

    Multiply both sides of the 1st Eq by -6.
    Multiply both sides of the 2nd Eq by 3.
    Then add the Eqs.

    -18a - 30b = -420
    +18a + 27b = 405

    -3b = -15
    b = 5.

    in the 1st Eq, replace b by 5:
    3a + 5*5 = 70
    3a = 70-25 = 45
    a = 15

  • Algebra 8th grade -

    62ab

  • Algebra 8th grade -

    lkmholjyul;ukyuj7y6gr48u565479
    +7+45236352478

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