Proving Lines Parallel (G.2d)

1. Proving Lines Parallel (G.2d) Objective : SWBAT determine if two lines are parallel (3.3) *hw/hw log/storybook/workbook p. 67 Warm-Up: worksheet 1-18 Homework (day 12)- check odd answers in text: p. 160 (7, 10, 12, 13-16, 17-26, 27-29) Bring Graph paper- Leave in notebook Quiz next block/Grade storybook Pearson Success due Friday

3. Copy and complete, then put behind your SOL divider

4. Answer questions on Unit 1 Test……… Story Time…….”Parallel Lines/Transversals”

5. Ways to Prove Two Lines Parallel • Show that corresponding angles are equal. • Show that alternate interior angles are equal. • Show that Alternate exterior angles are equal. • Show that consecutive interior angles are supplementary. • In a plane, show that the lines are perpendicular to the same line. Two Column Proofs: Statements and Reasons. Every Statement must have a reason and vice-versa (these are justifications). What can you use as reasons? Theorems (VARC), Properties(transitive, reflexive, distributive) Definitions of vocab: complementary, supplementary, congruent, midpoint, Postulates: angle bisector, segment addition GIVEN Lesson 2-5: Proving Lines Parallel

6. State which lines, if any, are parallel. Justify. m l p 67° q 113° 67°

12. Proving Lines Parallel • If two lines are cut by a transversal and corresponding angles are congruent, AB // CD. Lesson 2-5: Proving Lines Parallel

13. Proving Lines Parallel • If two lines are cut by a transversal and alternate interior angles are congruent, AB // CD. Lesson 2-5: Proving Lines Parallel

14. Proving Lines Parallel • If two lines are cut by a transversal and Alternate exteriorangles are congruent, AB // CD. Lesson 2-5: Proving Lines Parallel

15. Proving Lines Parallel - Postulates &Theorems If two lines are cut by a transversal and consecutive interior angles are supplementary AB // CD. Lesson 2-5: Proving Lines Parallel

16. Homework Answers (day 12)(odd answers are in your textbook)- please check them!!