8. Get Ready for Chapter 3  P.125 1-11

9. 3-1 PARALLELS

10. I. PARALLEL LINES

11. II. INTERSECTING LINES

12. III. SKEW LINES

15. IV. TRANSVERSALS

16. EXAMPLES 1. Name the plane parallel to plane AEF

17. 2. Which segment is skew to GH?

18. 3. How many segments intersect AM?

19. 4. Name a pair of consecutive interior angles

20. 5. Which statement is true about skew lines? A.They intersect B.They lie in the same plane. C.They are perpendicular D.They do not intersect.

21. 6. Identify:  a.Name all planes that are parallel to plane ABC.  b.Name all segments that intersect AB.  c.Name all segments that are parallel to KG.  d.Name all segments that are skew to TK.

22.  7. Texas is the leading producer of livestock in the United States. A diagram of a feed lot on a farm is shown below. Identify the sets of lines to which each given line is a transversal.  a.line kb.line sc.line p  d.line m

23. 8. Refer to the figure below. Identify each pair of angles as alternate interior, alternate exterior, corresponding, or consecutive interior angles.  a.  2 and  10  b.  9 and  7  c.  1 and  7  d.  12 and  8  e.  11 and  8  f.  4 and  12

24. Classwork  P. 128 1-21

25. 3-2 ANGLES

26. Corresponding angles 1 2 1 2 If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent.

27. Alternate Interior 3 4 3 4 If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent.

28. Consecutive Interior 5 6 m 5 + m 6 = 180° If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary.

29. Alternate Exterior 7 8 7 8 If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent.

30. Perpendicular transversal j k If a transversal is perpendicular to one of two parallel lines, then it is perpendicular to the other.

31. Examples 1. If < 3 = 108, find all other angles. 1 2 34 5 6 78 A B CD

32. 2. Use properties of parallel lines to find the value of x. S OLUTION Corresponding Angles Postulate m 4 = 125° Linear Pair Postulate m 4 + (x + 15)° = 180° Substitute. 125° + (x + 15)° = 180° Subtract. x = 40°

33. 3. Find the measure of <1 if < 1 = 8y – 6 and < 2 = 7y.

34. 4. Find y.

35. 5. If < 2 = 8x = 6 and <6 = 4x + 28, find x and < 6.

36. 6. In the figure, m  4 = 121. Find m  5.

37. 7. What is the measure of  ABC ?

38. 8. If m  1 = 16 x - 8, m  2 = 4( y + 8), and m  3 = 14 x + 2, find x and y.