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Math Help - value of q in the equation

  1. #1
    rcs
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    value of q in the equation

    i tried to make this equation into q-2x^2 / x = 3x/x but cant make it to the next step... there seem no other value for q

    how is it being shown ?


    thanks
    Attached Thumbnails Attached Thumbnails value of q in the equation-44.jpg  
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  2. #2
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    Re: value of q in the equation

    need a little help in this equation guys...
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    Re: value of q in the equation

    Your question is typed really awkwardly. I think it means

    \frac{q}{x} - 2x = 3 has 4 as a root (for x).

    If so, then x = 4...what are you struggling on?
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    Re: value of q in the equation

    im struggling on how to get the 4 roots of the equation but q is there.... the only move i can make this is to q/x = 3 + 2x ; q = (2x + 3) x ; q = 2x^2 + 3x... im stuck here... to find the roots of the equation...

    thanks
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    Re: value of q in the equation

    Are there four roots for x? Or is 4 a root?
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    Re: value of q in the equation

    because it is being indicated in the book i read... that is why ... how come it is 4... i wonder what number i have to manipulate here when there is x and q ... do i need to use discriminant here sir?
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    Re: value of q in the equation

    as i understood 4 roots for x so , q must have value
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    Re: value of q in the equation

    Clearly, there cannot be 4 roots. Multiplying both sides by x you obtain

    q - 2x^2 = 3x

    which is a second-degree polynomial, and only has two roots for x.
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    Re: value of q in the equation

    With q = 44 (and I don't see why 44 is picked!), then solution is x = 4 or -5.5;
    discriminant = 9 + 8q, so q => 9/8 for real solutions.
    I guess I can see q = 44 IF problem stated: one of the 2 solutions is a positive integer (4 in this case).
    (OR one of the solutions is a square...)
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    Re: value of q in the equation

    Yes, if the problem stated that 4 is a root, clearly, q = 44.
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    Re: value of q in the equation

    Quote Originally Posted by rcs View Post
    as i understood 4 roots for x so , q must have value
    That is, as you have been told, impossible. If you multiply both sides of q/x- 2x= 3 by x you get q- 2x^2= 3x which is a quadratic equation and has, at most, 2 distinct roots. The original equation might have fewer solutions, but cannot have more so NO value of q gives the equation 4 roots.

    If, on the other hand, you are saying that 4 is a root, we must have q/4- 2(4)= 3 so that q/4= 11 and then q= 44.

    What is the exact statement of the problem in your text? You posted a picture in your first post, but that is something you wrote. Could you post a picture of the problem in the text?
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  12. #12
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    Re: value of q in the equation

    Quote Originally Posted by HallsofIvy View Post
    That is, as you have been told, impossible. If you multiply both sides of q/x- 2x= 3 by x you get q- 2x^2= 3x which is a quadratic equation and has, at most, 2 distinct roots. The original equation might have fewer solutions, but cannot have more so NO value of q gives the equation 4 roots.

    If, on the other hand, you are saying that 4 is a root, we must have q/4- 2(4)= 3 so that q/4= 11 and then q= 44.

    What is the exact statement of the problem in your text? You posted a picture in your first post, but that is something you wrote. Could you post a picture of the problem in the text?
    This is it: What is the value of q so that (q/x) - 2x = 3 has 4 as a root?
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    Re: value of q in the equation

    Quote Originally Posted by rcs View Post
    This is it: What is the value of q so that (q/x) - 2x = 3 has 4 as a root?
    If so, then we've already solved it like five times. Why does the original problem say that it has 4 roots?
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    Re: value of q in the equation

    sorry sir... i must have overlooked it. but still i have to say thank you so much for the gift of intelligence you shared.

    Millions of Thanks
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