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Thread: Applications of Quadratic Equaiton

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    Applications of Quadratic Equaiton

    Applications of Quadratic Equaiton-question-17.jpg

    Applications of Quadratic Equaiton-original-question-17.jpg

    for question 17 i don't know where i went wrong

    Applications of Quadratic Equaiton-img_1404-1-.jpg
    Last edited by diehardmath4; Nov 25th 2017 at 07:29 PM.
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  2. #2
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    Re: Applications of Quadratic Equaiton

    Quote Originally Posted by diehardmath4 View Post
    Click image for larger version. 

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    Click image for larger version. 

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    for question 17 i don't know where i went wrong..
    Click image for larger version. 

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    Please do not think me petty; but this posting is unreadable.
    Why can you simply type out the question in clear type?
    There is no need to try to use symbols. sqrt{n^2+3n-6} is very clear as it stands.
    Putting \$ around \sqrt{n^2+3n-6} gives $\sqrt{n^2+3n-6}$

    OR at least take clear pictures that are orientated correctly.

    If you follow those suggestions you are more likely to get help.
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    Re: Applications of Quadratic Equaiton

    Applications of Quadratic Equaiton-right-side-up-mate.jpg

    Applications of Quadratic Equaiton-original-question-17.jpg
    Attached Thumbnails Attached Thumbnails Applications of Quadratic Equaiton-q17.jpg  
    Last edited by diehardmath4; Nov 26th 2017 at 03:58 PM.
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    Re: Applications of Quadratic Equaiton

    Can't tell what d'hell you're doing...

    Post your work yourself.
    Btw, the given answer is correct.
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    Re: Applications of Quadratic Equaiton

    this is my 2nd attempt for question 17

    Applications of Quadratic Equaiton-attempt-correct-.jpg
    Last edited by diehardmath4; Nov 26th 2017 at 05:01 PM.
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    Re: Applications of Quadratic Equaiton

    $N = \dfrac{1}{2}(n^2-n)$

    $2N = n^2-n$

    $0 = n^2-n-2N$

    $a=1$, $b=-1$, $c=-2N$

    $n = \dfrac{1 \pm \sqrt{1 -4(1)(-2N)}}{2(1)}$

    clean it up ... also note $n > 0$
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    Re: Applications of Quadratic Equaiton

    Your work shown on last picture is finally READABLE!

    BUT it shows you do not yet understand the basics,
    thus you need serious classroom help...
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    Re: Applications of Quadratic Equaiton

    For example, you start with N= \frac{1}{2}(n^2- n) and on the very next line have N= 2(\frac{1}{2}(n^2- n) that has two errors! First there is an end parenthesis missing. Yes, I know that was just a "typo" but such things can make you work very hard to follow. Second, you have multiplied by 2 on the right but not on the left. Again, that is probably just an oversight since you have the "2N" in the next line but such errors can lead to greater mistakes later on.

    Then you have \sqrt{2N}= \sqrt{(n- n} where you have again dropped ")"- though strictly speaking you don't need the parentheses at all. More importantly the " ^2 is missing.

    On the very next step, you still have the \sqrt{} on the left but it has disappeared from the right! And you still have the " n- n" instead of " n^2- n".

    It took me a while to figure out what in the world you had done to get the last line! You have apparently multiplied by n on the left side but added n on the right! And you are still missing the n^2. I agree with DenisB that you need to work with you teach on this.
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    Re: Applications of Quadratic Equaiton

    Is There any websites or videos i can watch you can refer me to ?
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    Re: Applications of Quadratic Equaiton

    Thanks from diehardmath4
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