L1.20 - Transformations, Transversals, and Proof
Learning Intentions and Success Criteria
[color=#ff0000]We are learning to:[/color][br][list][*]Prove (in writing) that when a transversal crosses parallel lines, alternate interior angles are congruent.[/*][*]Prove that when a transversal crosses parallel lines, corresponding angles are congruent.[/*][/list][color=#ff0000]We are successful when we can:[/color][br][list][*]Prove alternate interior angles are congruent.[/*][*]Prove corresponding angles are congruent.[/*][/list]
20.1: Math Talk: Angle Relationships
20.2: Make a Mark? Give a Reason.
1. Translate lines AE and CD by the directed line segment from B to C. Label the images of A, B, C, D, E as A’, B’, C’, D’, E’.[br][br]2. What is true about lines AE and A’E’? Explain your reasoning.
3. Take turns with your partner to identify congruent angles.[br][br][list][*]For each pair of congruent angles that you find, explain to your partner how you know the angles are congruent.[/*][*]For each match that your partner finds, listen carefully to their explanation. If you disagree, discuss your thinking and work to reach an agreement.[/*][/list]
20.3: An Alternate Explanation
1. Rotate line AE by 180 degrees around point C. Label the images of A, B, C, D, E as A’, B’, C’, D’, E’.[br][br]2. What is true about lines AB and A’B’? Explain your reasoning.
3. Take turns with your partner to identify congruent angles.[br][br][list][*]For each pair of congruent angles that you find, explain to your partner how you know the angles are congruent.[/*][*]For each match that your partner finds, listen carefully to their explanation. If you disagree, discuss your thinking and work to reach an agreement.[/*][/list]
Learning Intentions and Success Criteria
[color=#ff0000]We are learning to:[/color][br][list][*]Prove (in writing) that when a transversal crosses parallel lines, alternate interior angles are congruent.[/*][*]Prove that when a transversal crosses parallel lines, corresponding angles are congruent.[/*][/list][color=#ff0000]We are successful when we can:[/color][br][list][*]Prove alternate interior angles are congruent.[/*][*]Prove corresponding angles are congruent.[/*][/list]
Cool-Down: Transformations on Parallel Lines
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