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    In C4 Heinemann book, chapter 5, page-78, Mixed exercise 5K, question-10.


    I need this question. I can’t read A’s x-coordinate only (_,-1, 3) from my book. Anyone who has this book, please give me that coordinate number.

    For convenience, the question looks like:
    The point A has coordinates (_, -1, 3) and the point B has coordinates (10, -2, 2). The line l has vector equation r = i + j + k +………………………… €¦â€¦â€¦.so on [I could read rest of them].
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    (Original post by geton)
    In C4 Heinemann book, chapter 5, page-78, Mixed exercise 5K, question-10.


    I need this question. I can’t read A’s x-coordinate only (_,-1, 3) from my book. Anyone who has this book, please give me that coordinate number.

    For convenience, the question looks like:
    The point A has coordinates (_, -1, 3) and the point B has coordinates (10, -2, 2). The line l has vector equation r = i + j + k +…………………………⠀¦â€¦â€¦.so on [I could read rest of them].
    It's (7, -1, 3).
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    (Original post by LakHani_Hasnain)
    It's (7, -1, 3).
    Thank you
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    Well I worked it out VERY carefully and I still don't get the right answer if I use those formulas.

    (2,0,1) and (-1,3,4) , (-1,3,0) and (4,-2,5)
    Therefore r = (-1,3,4) + t(3,-3,-3) and r = (-1,3,0) + m(5,-5,5)
    Therefore the i and j components give simultaneous equations

    1) -1 + 3t = -1 + 5m
    2) 3 - 3t = 3 - 5mm

    If you add the equations they both cross out and you get no answer and likewise for substitution. What is wrong with this??
 
 
 
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