Name Class Date Practice 3-3 Form K Proving Lines Parallel Which lines or segments are parallel? Justify your answer. 1. 2. r t B D q s A J K L 4. M 102 68 112 40 E C AB n CD; Converse to Corresp. ' Thm.; BC n DE; Converse to Corresp. ' Thm. q n s; Converse to Alt. Ext. ' Thm. 3. 40 S N Q P O PK n MN; Converse to Same-Side Int. ' Post; NM n QJ and JM n QN; Given T U R XW V SX n UV ; Converse to Corresp. ' Thm. 5. Developing Proof Complete the flow proof below. 1 Given: /1 and /4 are supplementary. 2 Prove: a 6 b b 3 4 2 and 3 are supplementary. 1 and 4 are supplementary. Given 1 2 and 3 4 aIb Substitution Property Converse of Same-Side Int. Post. Vert. are . 6. Mrs. Jensen made a quilt for her nephew. The pattern for one block is shown at the right. If m/1 5 60 and m/2 5 115, are the two gray strips of fabric parallel? Explain. No; answers may vary. Sample: l1 and l2 are same-side int. '. For the strips of fabric to be n, l1 and l2 must be suppl., but 115 1 60 u 180. Prentice Hall Foundations Geometry • Teaching Resources Copyright © by Pearson Education, Inc., or its affiliates. All Rights Reserved. 25 a 1 2 Name Class 3-3 Date Practice (continued) Form K Proving Lines Parallel Algebra Find the value of x for which a n b. 7. 8. 65 a b (6x 17) (x 72) b 43 9. 143 a 21 10. a a (7x 2) (3x) (6x) b b (12x) (8x 14) 16 12 x Developing Proof Use the given information to determine which lines, if any, are parallel. Justify each conclusion with a theorem or postulate. s t 1 2 7 8 12 y 3 4 9 10 6 5 11. /8 is supplementary to /9. x n y; Converse of Same-Side Int. ' Post. 12. /7 > /4 13. /9 is supplementary to /12. s n t; Converse of Same-Side Int. ' Post. 14. /9 > /11 s n t; Converse Of Alt. Int. ' Thm. 11 x n y; Converse Of Alt. Ext. ' Thm. 15. Error Analysis A classmate said that AB 6 DC A W based on the diagram at the right. Explain your classmate’s error. You can’t prove that AB n DC with the information given because the congruent angles aren’t formed by the same transversal. D Z Algebra Determine the value of x for which c n d. Then find ml1 and ml2. 16. m/1 5 100 2 x, m/2 5 40 1 2x 20; 80; 80 1 c d 17. m/1 5 90 2 6x , m/2 5 100 2 8x 5; 60; 60 2 Prentice Hall Foundations Geometry • Teaching Resources Copyright © by Pearson Education, Inc., or its affiliates. All Rights Reserved. 26 Y C X B
© Copyright 2024