Midpoint of a Line Segment

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

Coordinates

Here we use Cartesian Coordinates to locate a point by how far along and how far up it is:

And when we know both end points of a line segment we can find the midpoint:

Midpoint of a Line Segment

The midpoint is halfway between the two end points:

  • Its x value is halfway between the two x values
  • Its y value is halfway between the two y values

To calculate it:

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

Midpoint of Line

 

We can use this formula:

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

Example: What is the midpoint here?

Midpoint of Line

Use the formula:

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

M = ( (−3)+8 2 , 5+(−1) 2 )

M = ( 5/2, 4/2 )

M = ( 2.5, 2 )