Showing posts with label Parallel line. Show all posts
Showing posts with label Parallel line. Show all posts

Tuesday, November 9, 2010

Ch. 5.3 Congruent Angles Associated With Parallel Lines



Today in class we learned that parallel lines imply that certain angles have certain properties.











Parallel Postulate: Through a point not on a line there is exactly one parallel to the given line.



by looking at this diagram we can assume a number of things













Angle 3 is congruent to Angle 8: Parallel lines imply congruent alt. int. angles





Any of the angles are either congruent or supplementary





Angle 1 is congruent to angle 6: Parallel lines imply congruent alt. ext. angles





Angle 2 is congruent to angle 5: Parallel lines imply congruent corr. angles





Angle 3 is supp. angle 5: Parallel lines cut by transversal implies supp. same side int. angles





Angle 2 is supp. angle 6: Parallel lines cut by transversal implies supp. same side ext. angles

On the image on left: If any of those two lines are parallel and one of them is parallel to the third all three are parallel