Watch these videos and take notes. The first video is an example of writing a linear equation in slope-intercept form to describe a real-world situation (in this case, a cost of a variable number of items). The second video is another example of a linear equation in slope-intercept form that describes a real-world situation. In the third video, the linear equation of a process (motion of the plane) is given. You will learn how to obtain the information about the motion from this equation.