Category Archives: Trigsted Chapter 2

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)

Graphing Linear Equations with Slope Intercept Form

Example: Graph the linear equation using the slope and the y-intercept. (the slope is positive and fractional)

Example: Graph the linear equation using the slope and the y-intercept. (positive and negative fractional slopes)

Example: Graph the linear equation using the slope and the y-intercept. (equation written in standard form)