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Thread: Quadratic formula help

  1. #1
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    Quadratic formula help

    http://i.imgur.com/bjFZw.jpg

    That's a picture of the problem.

    Where's I'm stuck is why
    (1.00 - x)(2.00 - x) = (2x)^2/49.7 = 0.0805x^2

    turns into

    0.920x^2 - 3.00x + 2.00 = 0

    What steps are the book skipping that I'm not following?

    Thankyou.
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  2. #2
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    (1.00 - x)(2.00 - x) = (2x)^2/49.7 = 0.0805x^2
    2 - 2x-x + x^2 = 2^2x^2/49.7
    2 - 3x + x^2 - 0.0805x^2 = 0.
    Now simplify.
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  3. #3
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    Did you just FOIL that or am I an idiot?
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  4. #4
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    Quote Originally Posted by climbo View Post
    Did you just FOIL that or am I an idiot?
    Yes. It is just FOIL.
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  5. #5
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    Not to beat a dead horse, but how do you simplify that?

    <br /> <br />
2 - 3x + x^2 - 0.0805x^2 = 0.<br />

    The steps confuse me to the point of no return. Don't judge me, I'm extremely rusty and very appreciative of your help.
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  6. #6
    Super Member bigwave's Avatar
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    combine like terms then reorder
    you should get the given answer
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  7. #7
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    Quote Originally Posted by climbo View Post
    Not to beat a dead horse, but how do you simplify that?

    <br /> <br />
2 - 3x + x^2 - 0.0805x^2 = 0.<br />

    The steps confuse me to the point of no return. Don't judge me, I'm extremely rusty and very appreciative of your help.
    Can't you subtract x^2 - 0.0805x^2?
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