Build & Fit Linear Functions

You can make a linear function by dragging the two GREEN points almost anywhere on the screen (why almost?). Alternatively, you can make a linear function by dragging a YELLOW point and a YELLOW "compass" (to set the slope). The linear function has a constant term an a term proportional to x Try to build the GREEN and/or the YELLOW linear function by combining the appropriate amounts of linear term and constant term using the BLUE sliders. Try to do this without looking at the expression for the linear function you have made. What questions could/would you pose to your students based on this applet ?