4,+Alternate+Interior+Angles+Theorem+and+Alteernate+Exterior+angles+Theorem

By: Elizabeth Daugherty, Maura Porter, and Molly Kaniger =ALTERNATE INTERIOR ANGLES THEOREM= __Definition: __ When two parallel lines are cut by a transversal, the resulting alternate interior angles are congruent. __Alternate Interior Angles__: //L//3 and //L//6 is an example of Alternate Interior Angles.





Ex. 1: Looking at the figure above, if //lines k and l are parallel//, locate the alternative interior angles. According to the Alternative Interior Angles theorem, are these angles congruent? line y and z are parallel, name the alternating interior angles Answers Ex. 1- 2&8, 3&5. Yes.

Prove the Alternate Interior Angles theorem 2. Given L1 || L2 Prove 4 is congruent to 6

Answer: 1. L1 || L2 Given 2. 4 is congruent to 8 Corresponding Angles Postulate 3. 8 is congruent to 6 Vertical Angles Congruence Theorem 4. 4 is congruent to 6 Transitive Property of Congruence

=ALTERNATE EXTERIOR ANGLES THEOREM= __Definition:__ When two parallel lines are cut by a transversal, the resulting alternate exterior angles are congruent. __Alternate Exterior Angles__: //L//1 and //L//8 is an example of Alternate Exterior Angles.   Ex. 1: Looking at the figure above, if lines k and l are parallel, locate the alternate exterior angles. Are these angles congruent? Why or why not?

name alternating exterior angles Answers Ex. 1: 1,7 4,6. Yes, due to the Alternate Exterior Angles Theorem.