coordinates of midpoint


The coordinates of the midpointMathworldPlanetmathPlanetmathPlanetmath of a line segmentMathworldPlanetmath are the arithmetic meansMathworldPlanetmath of the coordinates of the endpointsMathworldPlanetmath of the segment. Thus, if the endpoints are  (x1,y1)  and  (x2,y2),  then the midpoint is

(x1+x22,y1+y22).

For justifying the above coordinates of the midpoint, we know that its abscissaMathworldPlanetmath x0 halves on the x-axis the line segment between x1 and x2. Since the lengths of the half-segments are x0-x1 and x2-x0, if  x1<x2,  and their opposite numbers, if  x2<x1,  in any case we can write

x0-x1=x2-x0.

Solving this equation for x0 yields:  x0=x1+x22.  result is gotten for the ordinate of the midpoint.

Title coordinates of midpoint
Canonical name CoordinatesOfMidpoint
Date of creation 2013-03-22 17:31:07
Last modified on 2013-03-22 17:31:07
Owner pahio (2872)
Last modified by pahio (2872)
Numerical id 5
Author pahio (2872)
Entry type Result
Classification msc 51N20
Classification msc 51M15
Classification msc 51-00
Related topic ConjugateDiametersOfEllipse
Related topic CentreOfMassOfPolygon
Related topic Midpoint4