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Math Help - Quadratic Equation Hidden, ax^2+bx+c=0

  1. #1
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    Quadratic Equation Hidden, ax^2+bx+c=0

    Hey all,

    I need help with this equation. It is a hidden equation which I have tried to solve on my maths booklet.

    The steps that must be followed are:

    ax^2 + bx + c = 0

    I have to use the quadratic formula and tranpose the above

    here is my question

    1 / R + R = 3 + 7 / R


    I need to get the A , b , c and plug it in the quadratic formula but the issue is i don't get the right answer which is 4.37, I believe I get the wrong A , B , C values at the start.



    If i need to be more specify please tell me.
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  2. #2
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    Take your equation and multiply each side by R to get rid of frcations.
    This will give you 1 + R^2 = 3R + 7.
    Move everything over to the left to get: R^2 - 3R - 6= 0.
    So a=1, b=-3, c=-6.
    Then use the quadratic formula!
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  3. #3
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    thank you so much it works.
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  4. #4
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    Glad to help!
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  5. #5
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    cool
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  6. #6
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    Quote Originally Posted by learner123 View Post
    I need to get the A , b , c and plug it in the quadratic formula but the issue is i don't get the right answer which is 4.37,......
    4.37 is approximate, plus there is a 2nd solution:
    [3 + sqrt(33)] / 2 = 4.37228...
    [3 - sqrt(33)] / 2 = -1.37228...
    Make sure you get that straight: it'll make your future life easier
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