This applet allows a person to plot points on the first quadrant of a Cartesian plane. Click on the canvas to plot points on the graph, then use the controls below it to adjust your red regression line. By checking Show Best Fit, the computer will calculate the best fit line of the data points, colored blue, and show it on the graph.
The accuracy meter measures how well your red line fits the data points. If the meter shows high accuracy, then the red line is a good fit to the data.