This document provides instructions for using a TI-Nspire calculator to demonstrate the midpoint formula. It describes how to: 1) Create a graph window and add two points, labeling them and assigning them to variables x1, x2, y1, y2. 2) Create a split screen with a spreadsheet and enter the midpoint formula using the variables to calculate the x- and y-coordinates of the midpoint as (x1 + x2)/2 and (y1 + y2)/2. 3) Manipulate the points in the graph to dynamically update the midpoint coordinates calculated in the spreadsheet.

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TI-Nspire Mini-Tutorials
Midpoint Formula Template
Summary of Keystrokes
Create a graph window and add two points:
c12/Gb 7 1 ·
(Use ¤ ¡ ` ¢ to move the pointer to the second point.) ·
Label the points and map them to variables x1, x2, y1, y2:
b 1 7 (Use ¤ ¡ ` ¢ to move the pointer to the first point.) a (Use
¤ ¡ ` ¢ to move the pointer to the second point.) a
d (Use ¤ ¡ ` ¢ to move the pointer to the x coordinate of the first point.)
a / h X 1 · (Repeat for x2, y1, and y2.)
a/hY1·a/h
X2·a/hY2·
Create a split screen with a spreadsheet:
Press the DOC key.
522/eb4
X · = ( X 1 + X 2 ) p 2 · (You will be asked
if the x1 and x2 refer to the variables you created or the cell references in the
spreadsheet. Select the Variable Reference option and click OK. Do these for each
variable.)
¤¤ae·¢``Y·=(Y1+Y2)
p2·¤¤ae·
Manipulate the points in the graph and watch the spreadsheet recalculate the
midpoint:
/e`¢¤¡a¡