a. Why are the lines whose equations are y = 1/3 x + 1 and y = -3x - 2 perpendicular?
b. Use a graphing utility to graph the equations in a [-10, 10, 1] by [-10, 10, 1] viewing rectangle. Do the lines appear to be perpendicular?
c. Now use the zoom square feature of your utility. Describe what happens to the graphs. Explain why this is so.