How to Construct a Midpoint with the TI-84 Plus

By C. C. Edwards

With GeoMaster on the TI-84 Plus graphing calculator, you can construct the midpoint of an already constructed segment or the midpoint between two existing points. The segment can be the side of a triangle or polygon. GeoMaster recognizes only those points that appear on the screen as small squares.

To construct a midpoint, first select the Midpoint tool from the DRAW menu (press [GRAPH][WINDOW], repeatedly press


to highlight the Midpoint tool, and press [ENTER]). If you are constructing the midpoint of a segment, use the arrow keys to place the cursor on the segment and press [ENTER] to construct the midpoint. If you are constructing the midpoint between two points, move the cursor to the first point and press [ENTER].

Then move the cursor to the second point and press [ENTER] to have GeoMaster construct the midpoint.

After constructing the first midpoint, the Midpoint tool remains active so that you can construct more midpoints. When you are finished constructing midpoints, press [CLEAR] to deactivate the Midpoint tool or select another menu item.