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Math Help - Make x the subject

  1. #1
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    Make x the subject

    I thought I was getting the hang of Algebra but this question has had me stumped all day.

    Y=(XY+2)/(3X-4)

    make X the subject.

    Apparently the answer is X=(2Y+1)/Y

    I can't get anywhere near the answer. Any help would be appreciated.
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  2. #2
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    Quote Originally Posted by futureprof View Post
    I thought I was getting the hang of Algebra but this question has had me stumped all day.

    Y=(XY+2)/(3X-4)

    make X the subject.

    Apparently the answer is X=(2Y+1)/Y

    I can't get anywhere near the answer. Any help would be appreciated.
    Multiply through by (3X-4)

    Y(3X-4) = XY+2<br />
    Distribute Y on the left:

    3XY-4Y = XY+2

    Spoiler:
    Bring X on one side

    <br />
3XY-XY = 2+4Y

    Factor 2 on the right

    2XY = 2(1+2Y)

    2 will cancel and divide by Y

    X = \frac{1+2Y}{Y}
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  3. #3
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    Thankyou.

    After all that it was really quite simple.

    Practice, practice, practice. I think that is what I need.
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