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Math Help - quadratic formula

  1. #1
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    quadratic formula

    3x(x-3)= -4

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  2. #2
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    3x(x-3)= -4

    3x^2-9x= -4

    3x^2-9x+4= 0

    a=3,b=-9,c=4

    Was that o.k?
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  3. #3
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    Quote Originally Posted by kelsikels View Post
    3x(x-3)= -4
    3x^2-9x+4=0???????
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  4. #4
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    what about the second part?
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  5. #5
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    Quote Originally Posted by kelsikels View Post
    what about the second part?
    What second part?
    Do you mean the complete solution?
    Oh no! That is your job!
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  6. #6
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    Quote Originally Posted by kelsikels View Post
    what about the second part?
    The formula is x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}

    Pickslides has given you values for a, b and c
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  7. #7
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    Quote Originally Posted by pickslides View Post

    a=3,b=-9,c=4
    Substitute these values into

    x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}
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  8. #8
    Super Member bigwave's Avatar
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    Cool

    here's a graph of 3x^2-9x+4= 0 if it is of any interest
    the x intercepts are not as obvious as they look.
    as mentioned already the quadradic equation will give the intercepts

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