2.1 Graphing, Midpoint

Finding the Midpoint

The Midpoint Formula

Suppose A is ( x_1,   y_1) and B is ( x_2,    y_2)

The midpoint of the line segment joining points A and B is given by the following formula.

( {x_1+x_2}/2,   {y_1+y_2}/2)

Example: Find the midpoint of a line segment joining points A and B.

Point A is ( 4, -2) and point B is ( -8, 3)

The x coordinate of the midpoint can be found by averaging the x-values of point A and B.  The y-coordinate of the midpoint can be found by averaging the y-values of point A and B.

( {4+(-8)}/2,   {-2+3}/2)

( {-4}/2,   {1}/2)

( -2,   {1}/2)