Graphing Calculator Activity: Trend Line and Line of Best Fit
In this series of activities, students learn how to use the sketch of a trend line to make a prediction about other values within the data. Then, students learned to write the equation of the trend line and make predictions using the equation the wrote down. This led into a graphing calculator activity, where students found the line of best fit using the Linear Regression function on the TI-83 calculators.
Before students started working with the calculators, we did a class example using the first problem on the worksheet below. We graphed the scatter plot manually, and students graphed their own trend line and found the equation of the trend line to see how different the answers may be for larger sets of data. This led us in to the most accurate trend line, or Line of Best Fit, activity below.