Question

what is the ruler postulate and when is it used
plz help

Answer 1

Ruler Postulate
The ruler postulate states that:

1.Every point on a line can be paired with a real number.
2.The number associated with a point A on the line is called the coordinate of A.
3.Two arbitrary points can be paired with the numbers 0 and 1, defining the length of a unit.
4.The distance between any two points <var>A</var> and <var>B</var> is designated AB.
5.The distance between two points A and B can be found by taking the absolute value of the difference of their coordinates: AB = |A - B|. Note that this implies that a distance is always positive.



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Answer 2

http://www.geom.uiuc.edu/~demo5337/Group3/distanc2.html