Education Technology

Meet You at the Intersection: Solving a System of Linear Equations

Activity Overview

In this activity, students' will collect and analyze motion data in order to determine the solution to a linear system of equations. They graph two motions on a common axis and find their intersection.

Before the Activity

  • Connect the motion detectors to the DIG/SONIC port of each of the CBL 2™ or to the DIG/SONIC 1 and DIG/SONIC 2 ports of the Vernier LabPro®
  • Connect the data collection devices to the calculators using the Unit-to-Unit cable
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 301 - 309 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to your class.

    Follow the Activity procedures:

  • Set up the motion detectors on a table, about 2 meters apart and parallel to each other
  • Simultaneously, make one person walk toward the first motion detector, and another person walk away from the second motion detector and begin data collection
  • Record the position and time at which the two persons cross each other
  • As data collection ends, transfer the data of the first calculator into the second one and observe the distance versus time graphs on the calculator
  • Trace through the plot and record the slopes of the lines, and the coordinates of the point of intersection on the Data Sheet
  • Write down a linear equation for each line and algebraically find the intersection of the two lines
  • After the Activity

    Students' will analyze their data and complete the Data Collection and Analysis Sheet. They also answer questions listed in it.

    Review student results

  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary