Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Analytic Geometry

9-12

40 Minutes

• ##### Device
• TI-Nspire™ CX/CX II
• TI-Nspire™ CX CAS/CX II CAS
• TI-Nspire™
• TI-Nspire™ CAS
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

3.2

## Midpoints in the Coordinate Plane

#### Activity Overview

Beginning with horizontal or vertical segments, students will show the coordinates of the endpoints and make a conjecture about the coordinates of the midpoint.

#### Key Steps

• On page 1.3, students will first see a line segment and the coordinates of the endpoints displayed.  Students should then make a prediction about the coordinates for the midpoint of the segment.

• On page 2.2, students will first see a diagonal segment and the coordinates of the endpoints.  Students can then drag the endpoints to create a different diagonal segment and make a prediction for the new coordinates of the midpoint.

• You can discuss how to calculate the coordinates of the midpoint of a segment if the coordinates of the endpoints are know.  Then, challenge students to write a formula or a rule for calculating midpoints.