Least Squares Line

This applet demonstrates the usage of the least squares method for determining the line of "best fit". Move the points around and see the square of the distance between a line and the points. Try to find adjust this line [red] to make the total as small as possible. The line of best fit [green] is the line that minimizes this sum using partial differentiation (from calculus).
1. Note the sum of the square distances is displayed on the right, can you adjust the red line to make this value as small as possible? 2. Click the "Show Least Squares Line", how close were you?