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# C4 Edexcel –Vector watch

1. 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].
2. (Original post by geton)
In C4 Heinemann book, chapter 5, page-78, Mixed exercise 5K, question-10.

I need this question. I canâ€™t read Aâ€™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€¦â€¦â€¦â€¦â€¦â€¦â€¦â€¦â€¦â €¦â€¦â€¦.so on [I could read rest of them].
It's (7, -1, 3).
3. (Original post by LakHani_Hasnain)
It's (7, -1, 3).
Thank you
4. 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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