The equations $y=2x$y=2x, $y=2x+6$y=2x+6 and $y=2x-8$y=2x−8 have been graphed on the same number plane:
What do all of the equations have in common?
What do you notice about the graphs?
What can you conclude from the answers above?
Identify, through investigation, properties of the slopes of lines and line segments (e.g., direction, positive or negative rate of change, steepness, parallelism, perpendicularity), using graphing technology to facilitate investigations, where appropriate