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How to know direction of point

  1. Jun 7, 2010 #1

    Refering to the attachment, we have set of points A,B,C,D which intersects at a point (Refer Figure)

    I have written a forumla in excel to calculate distance d1,d2,d3,d4 from this intersection point.

    How would i know that d2 distance is negative ( or in a reverse position) without actually comparing the X,Y positions with respect to Intersection Point.

    Is there any other way to do it. ?


    Attached Files:

    • ABCD.JPG
      File size:
      16.6 KB
  2. jcsd
  3. Jun 7, 2010 #2


    Staff: Mentor

    Your attachment is pending approval, so I don't know the details of your problem.

    You should not get a negative distance, so if you are, you are doing something wrong. Assuming that your points are in the plane, the distance from a point A(a, a2) to point B(b1, b2) is
    [tex]\sqrt{(b_1 - a_1)^2 + (b_2 - a_2)^2}[/tex].
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