Midpoint of a Line Segment

graph with point (12,5)

Coordinates

We will be using Cartesian Coordinates, where we mark
a point on a graph by how far along and how far up it is.

Example: The point (12,5) is
12 units along, and 5 units up
 

Midpoint of a Line Segment

The midpoint is halfway between two points.

So all we have to do is ...

... calculate the average x and average y of the two end points:

  • Add both "x" coordinates, divide by 2
  • Add both "y" coordinates, divide by 2

 

Midpoint of Line

And this is what you get:

M = ( xA+xB , yA+yB )
2 2

 

Example: What is the midpoint here?

Midpoint of Line  
M = ( xA+xB , yA+yB )
2 2

M = ( -3+8 , 5+(-1) )
2 2

M = ( 5/2, 4/2 )

M = ( 2.5, 2 )