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    Hi, the equation is (4x) over (x-1) = (6) over (x-3)

    I have cross multiplied, expanded then made the quadratic equal 0. Then I have tried to solve using the quadratic formula and have the answer:

    (+18 +/- root 228) over 8 but the answer in the book is (+9 +/- root 57) over 4

    but by simplifying my answer wouldn't I get (+9+/- root 114) over 4 instead of root 57?

    So I am stuck

    I am grateful for any help


    Thanks
    Millie
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    (Original post by Peace&Love)
    Hi, the equation is (4x) over (x-1) = (6) over (x-3)

    I have cross multiplied, expanded then made the quadratic equal 0. Then I have tried to solve using the quadratic formula and have the answer:

    (+18 +/- root 228) over 8 but the answer in the book is (+9 +/- root 57) over 4

    but by simplifying my answer wouldn't I get (+9+/- root 114) over 4 instead of root 57?

    So I am stuck

    I am grateful for any help


    Thanks
    Millie
    If you take a factor 2 inside a square root it becomes a factor of 4

    Does this answer your question?
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    (Original post by Peace&Love)
    Hi, the equation is (4x) over (x-1) = (6) over (x-3)

    I have cross multiplied, expanded then made the quadratic equal 0. Then I have tried to solve using the quadratic formula and have the answer:

    (+18 +/- root 228) over 8 but the answer in the book is (+9 +/- root 57) over 4

    but by simplifying my answer wouldn't I get (+9+/- root 114) over 4 instead of root 57?

    So I am stuck

    I am grateful for any help


    Thanks
    Millie
    \sqrt{228}=\sqrt{4} \times \sqrt{57}

    Then using this you can take out a factor of 2 from the numerator and the denominator and cancel to leave you with that desired answer.
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    (Original post by Robbie242)
    \sqrt{228}=\sqrt{4} \times \sqrt{57}

    Then using this you can take out a factor of 2 from the numerator and the denominator and cancel to leave you with that desired answer.

    Thanks so much I now understand
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    it is easier to divide out a common factor in the quadratic equation before you use the formula.
 
 
 
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