Write each question and answer it on your own paper to find a relationship between the slopes of parallel lines and the slopes of perpendicular lines.

1. Name each line in the picture. [br] Black: [br] Red:[br]  Purple:[br] 2. Which lines are parallel? What are their slopes?[br] 3. Which lines are perpendicular? What are their slopes?[br] 4. Now, drag point A until the slope of the black line is 3. [br] 5. What is the slope of the red line now? [br] 6. What is the slope of the purple line now?[br] 7. Make a conjecture (prediction) about the slopes of parallel lines.[br] 8. Make a conjecture about the slopes of perpendicular lines.[br][br][b]Further Investigation[/b][br]Can parallel lines have the same y-intercept? Explain why or why not.[br][br]Can perpendicular lines have the same y-intercept? Explain why or why not.[br][br][br]