Difference between revisions of "Centroid"

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{{stub}}
 
{{stub}}
  
The '''centroid''' of a [[triangle]] is the point of intersection of the [[triangle median |medians]] of the triangle.  The centroid has the special property that, for each median, the distance from a vertex to the centroid is twice that of the distance from the centroid to the midpoint of the side opposite that vertex.  Also, the three medians of a triangle divide it into six regions of equal area.
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The '''centroid''' of a [[triangle]] is the point of intersection of the [[median of a triangle |medians]] of the triangle and is generally denoted <math>G</math>.  The centroid has the special property that, for each median, the distance from a vertex to the centroid is twice that of the distance from the centroid to the midpoint of the side opposite that vertex.  Also, the three medians of a triangle divide it into six regions of equal area.
 
The centroid is the center of mass of the triangle; in other words, if you connected a string to the centroid of a triangle and held the other end of the string, the triangle would be level.
 
The centroid is the center of mass of the triangle; in other words, if you connected a string to the centroid of a triangle and held the other end of the string, the triangle would be level.
  
 
The coordinates of the centroid of a [[coordinatize]]d triangle is (a,b), where a is the arithmetic average of the x-coordinates of the vertices of the triangle and b is the arithmetic average of the y-coordinates of the triangle.   
 
The coordinates of the centroid of a [[coordinatize]]d triangle is (a,b), where a is the arithmetic average of the x-coordinates of the vertices of the triangle and b is the arithmetic average of the y-coordinates of the triangle.   
  
(pictures needed)
 
  
(proofs of these properties anyone?)
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<center>[[Image:centroid.PNG]]</center>
 
 
(example problems?)
 
  
  
  
 
== See also ==
 
== See also ==
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* [[Cevian]]
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* [[Geomtry]]

Revision as of 11:11, 30 July 2006

This article is a stub. Help us out by expanding it.

The centroid of a triangle is the point of intersection of the medians of the triangle and is generally denoted $G$. The centroid has the special property that, for each median, the distance from a vertex to the centroid is twice that of the distance from the centroid to the midpoint of the side opposite that vertex. Also, the three medians of a triangle divide it into six regions of equal area. The centroid is the center of mass of the triangle; in other words, if you connected a string to the centroid of a triangle and held the other end of the string, the triangle would be level.

The coordinates of the centroid of a coordinatized triangle is (a,b), where a is the arithmetic average of the x-coordinates of the vertices of the triangle and b is the arithmetic average of the y-coordinates of the triangle.


Centroid.PNG


See also