PTA (Parallel Lines, Transversals and Angles)

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SWBAT identify and apply relationships created by angles formed by parallel lines cut by a transversal.

Big Idea

Students will draw and measure to discover relationships of angles formed by parallel lines cut by a transversal.

Do Now

10 minutes

Students will review identifying angles like alternate interior, alternate exterior, corresponding, and consecutive interior angles.  You should note that question #3 has none of these relationships. 

Exploration #1 and #2

35 minutes

The video narrative explains the two explorations and how they exemplify math practice standards 3 (viable arguments and critiques) and 6 (attend to precison).

Practice with Angles

15 minutes

Teachers can lead students through these application with algebra questions for further practice of using angle relationships given 2 parallel lines cut by a transversal.  Question #1 focuses on numerical application, while questions #2-4 focus on utilizing algebra skills.  You should be wary of question #3 as most students will find x, and then stop.  This is a great chance for you to warn students about this "trap" which is frequently on the SATs as well.


10 minutes

Students will work in small groups or independently to complete the activity if time remains.  If time is limited in class this can become a homework assignment.

Exit Ticket

10 minutes

Students will find the measure of an angle algebraically based on the knowledge that consecutive interior angles are supplementary.