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    I have my final exam tommorow which is 30% of the grade and I can't solve these sample questions. I need help!!!! Thanks.
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    please help me.... T.T i have exams tommrow
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    argh..............
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    which exam is that? All of them ??? and you need help at this time ??
    Ok, I'll try the 1st
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    thank you so much!!! i have my high school math exam tommorow!!! and it's only 9pm cuz its canada
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    Do you know about the meeting point of median lines in a triangle ???

    --------------

    My suggestion is:
    You take X' is the midpoint of CD, then you prove that AX' cuts BD at O' which statisfies: BO' = O'D.

    -> O' = O => X' = X.

    --------------

    I need to go to sleep btw It's very very late here. Sorry
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    i have to use vector method.... there is going to be number of vector proof question on the exam
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    (Original post by jeongsuman)
    i have to use vector method.... there is going to be number of vector proof question on the exam
    Ah, ok, then let a = AB, b = AD
    I am sure you can find the expression of AO in term of a and b

    Then you may find CX and DX in tems of a and b
    You'll see CX = XD
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    how????? -_-
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    (Original post by jeongsuman)
    how????? -_-
    It seems too late now. Yesterday, I had to go to bed, that time was 3am already, and I had lecture at 9am. Sorry.

    Let AB = a, AD = b

    =>AC = a + b

    So AO = 1/3 a + 2/3b

    Let |DX|/|DC| = k

    => 1-k = |XC|/|DC|

    So AX = kAC + (1-k)AD = k(a +b) + (1-k)b

    => AX = ka + b

    Since AX has the same direction with AO

    Then compare the coefficients of a and b we have
    k÷(1/3) = 1÷(2/3)
    Then you'll get k = 1/2

    So DX = XC = 1/2DC
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    the same question appeared on the exam and i couldn't solve it... anyway thanks for solving the question
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    So did you do well with other questions??
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    yes other questions were pretty straightforward
 
 
 
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