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Math Help - simple equation

  1. #1
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    simple equation

    d+8/d-2=9/4

    Thankful for help. Now I don't get how to write this. d+8 should be the numerator, d-2 the denominator. How do i get that?
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  2. #2
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    Hi

    \frac{d+8}{d-2} = \frac94

    First note that d \neq 2 because the denominator must not be equal to 0

    Multiply both sides by (d-2)

    d-2) = \frac94\d-2)" alt="\frac{d+8}{d-2} \d-2) = \frac94\d-2)" />

    d-2)" alt="d+8 = \frac94\d-2)" />

    Multiply both sides by 4
    4(d+8) = 9(d-2)

    Spoiler:
    Expand both sides
    4d+32 = 9d-18

    32 = 9d-18-4d = 5d-18

    32 + 18 = 5d

    5d = 50

    d = 10
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  3. #3
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    Quote Originally Posted by strunz View Post
    d+8/d-2=9/4

    Thankful for help. Now I don't get how to write this. d+8 should be the numerator, d-2 the denominator. How do i get that?
    There is a latex tutorial somewhere. You can type this problem as I have done below and click on someone's text to see what they typed.

    \frac{d+8}{d-2} = \frac{9}{4}

    Multiply both sides by (d-2) to give

    d+8 = \frac{9d}{4} - \frac{9}{2}

    \frac{9d-4d}{4} = -\frac{9-16}{2}

    Then multiply by 4/5 to get your answer
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