Education Technology

Getting Down to Basics

Published on 06/09/2008

Activity Overview

In this activity, students explore linear equation models for real-life situations. They learn to find a linear equation when two pairs of related points are on a line.

Before the Activity

  • See the attached PDF file for detailed instructions for this activity
  • Print pages 7 - 13 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Use the values for the freezing temperature of water (32° F, 0° C) and the boiling temperature of water (212° F, 100° C) as data points
  • Use the data points to calculate the slope of the linear model that can be used to find the conversion formula (Fahrenheit and Celsius readings)
  • Divide the change in the y-value and in x-value to find rate of change and thus the slope
  • Substitute one of the ordered pairs into the equation y = mx + b, and find the y-intercept
  • Use values of m and b to write the equation for converting temperature in Celsius (y-value) to Fahrenheit (x-values)


  • Given coordinates of two points on a line, use the slope formula m = (y2 - y1)/(x2 - x1) to find the slope m
  • Find the y-intercept
  • Write the slope intercept form of the equation


  • Write a simple program on the Voyage 200 PLT to find a linear model for any two points


  • Solve real world problems using linear models expressed in slope-intercept form
  • After the Activity

    Review student results:

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