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