**How to Use the Interactive Figure**

This interactive figure allows the user to manipulate both the points and the line to observe the effects on the sum of residuals shown at the bottom of the figure.

Modify Line: Checking this box allows the user to modify the placement of the line in two ways: (*a*) by dragging the line, the user rotates the line around a the *y*-intercept, thus changing the slope of the line without changing the *y*-intercept; and (*b*) by dragging the point at the *y*-intercept, the user translates the line without changing its slope. To disable this capability, click on the checked box to clear the check.

Modify Points: Checking this box allows the user to modify the placement of the points. Once the box is checked, the user can change the position of any red point by clicking on that point and dragging it to a different position.

Squares: This button allows the user to choose the square of the vertical distance between each point and the line, or "distance squared," as the mode of calculation for the equation at the bottom of the figure.

Absolute Value: This button allows the user to choose the "absolute value" of the vertical distance between each point and the line as the mode of calculation for the equation at the bottom of the figure.

Shortest Distance: This button allows the user to choose the perpendicular distance, or "shortest distance," between each point and the line as the mode of calculation for the equation at the bottom of the figure.