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Math Help - The quadratic formula

  1. #1
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    Smile The quadratic formula

    Use the quadratic formula to solve:

    -4x^2 + 13x - 3 = 0
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  2. #2
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    # infront of x^2 is a
    infront on x is b
    infront of nothing constant term is c

    also make sure equation is in standard form which it is.


    then fill into

    x= -b sqrt (b^2 -4ac)
    2a
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  3. #3
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    Quote Originally Posted by brentwoodbc View Post
    # infront of x^2 is a
    infront on x is b
    infront of nothing constant term is c

    also make sure equation is in standard form which it is.


    then fill into

    x= -b sqrt (b^2 -4ac)
    2a
    Yes, I tried that but I didn't get the right answer.
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  4. #4
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    make sure you keep track of negatives "2 neg. = pos."
    also what is the given answer?
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  5. #5
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    also its + the sqrt sorry so -b plus or minus the sqrt
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  6. #6
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    I get x=1/4,3
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  7. #7
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    I got 2 √6 instead of 7 5√2.

    EDIT: Sorry, I meant I got -13 √217/ -8 instead of 9 √89/ 2.
    Last edited by Joker37; November 28th 2008 at 10:45 AM.
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  8. #8
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    Quote Originally Posted by Joker37 View Post
    I got 2 √6 instead of 7 5√2.
    thats odd maybe someone else can chime in on this but I get

    -13 +/- √121
    -8


    and 121 is a perfect square so

    -13 +/- 11
    -8

    so

    1/4 , 3
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