3.4+Proving+Lines+Parallel

In this lessons we learned how to prove that two lines are parallel. We learned how to prove them by the corresponding angles which if the two lines are parallel the angles are congruent. We also learned that if the alternate exterior or alternate interior angles will be congruent if the lines are parallel. Another way we learned to prove the parallel lines was the consecutive interior angles which will add up to 180 degrees if the lines are parallel. All of these concepts can be applied to lines in real life.
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Answer: No the lines are not parallel. pg. 152 example 5

Are these lines parallel? If so how would you prove them to be parallel? pg. 153 #3 Answer: Yes, alternate exterior

Answer: Yes, Corresponding angles pg.153 #7

Vocabulary: Parallel Lines- two lines that go on forever and will never touch

Transversal- Line cutting through two parallel lines. The transversal is used to prove if lines are parallel or not.

Corresponding angles- Angles on the same side of the transversal that if congruent the lines are parallel. Seen in number 3 above. p.150

Alternate Exterior/Interior Angles- two angles on opposite sides of the transversal. Exterior are seen above in problem number two. Interior are the same but on the inside of the 2 lines.

p.150

Consecutive Angles- two angles in between the two parallel lines that are on the same side they will add up to 180 degrees if the two lines are parallel p.150

Vertical Angles- two angles that are formed by the transversal with the same line these lines are congruent. In the extra problem below (number 4) an example would be angle a and angle c.

Extra problems: 3 extra problems** #4: Find the measure of angle d
 * do all 3

Answer: 72 degrees @http://www.tutorvista.com/content/math/geometry/lat/question-answers2.php