is different from the point 
because of the rule that the first number appearing in the triple represents the 
-coordinate, the second number the 
-coordinate, and so on.
is: a set of numbers or quantities arranged, according to a certain rule, to represent an entity and such that any change in the order represents a change (or a potential change) in the represented entity.
is exemplified: by the ordered triple representing the coordinates of a point in three-dimensional space; the point is different from the point because of the rule that the first number appearing in the triple represents the -coordinate, the second number the -coordinate, and so on.
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