1. Transversals & Special Angles
Objectives:
1.) To identify transversals
2.) To identify angles formed by lines and their transversals
4/26/2017
Mrs. McConaughy Geometry

2. Mrs. McConaughy Geometry
Definition
A transversal is a line that intersects two or more coplanar lines in two or more distinct points.
4/26/2017
Mrs. McConaughy Geometry

3. Example 1 Is line t a transversal? Explain. t t m r n t s x y
4/26/2017
Mrs. McConaughy Geometry

4. Mrs. McConaughy Geometry
Example 2
Identify each transversal in the figure. A
B C
AC AB BC
4/26/2017
Mrs. McConaughy Geometry

5. Special Angle Pairs Formed by Two Lines and a Transversal
Recall, linear pairs of angles and vertical angles!
Special Angle Pairs Formed by Two Lines and a Transversal
When a transversal intersects two lines, some special angle pairs are formed.
4/26/2017
Mrs. McConaughy Geometry

6. Special Angle Pairs Formed by Two Lines and a Transversal
1 2
3 4
5 6
7 8
Alternate Interior Angles
Corresponding Angles
1 2
3 4
5 6
7 8
1 2
3 4
5 6
7 8
Alternate Exterior Angles
Same-Side Interior Angles
4/26/2017
Mrs. McConaughy Geometry

7. Mrs. McConaughy Geometry
Example 3
Identify each given pair of angles as alternate interior, corresponding, alternate exterior, or none of these.
1 & 8
3 & 7
4 & 5
2 & 8
3 & 5
7 8
Determine the following:
Corresponding Angles:
< 7 & < 3; < 5 & < 1
< 8 & < 4; < 6 & < 2
Alternate Interior Angles:
< 5 & < 4; < 6 & < 3
Alternate Exterior Angles:
< 7 & < 2; < 8 & < 1
Same-side Interior Angles:
< 5 & < 3; < 6 & < 4
4/26/2017
Mrs. McConaughy Geometry

8. Final Checks for Understanding
1. Define transversal.
2. Given l // m, cut by transversal s, in the figure which follows, name the following:
Corresponding Angles:
Alternate Interior Angles:
Alternate Exterior Angles:
Same-side Interior Angles:
4/26/2017
Mrs. McConaughy Geometry

9. Final Checks for Understanding
l m r s
Given l // m, cut by transversal s, name the following:
Corresponding Angles:
Alternate Interior Angles:
Alternate Exterior Angles:
4/26/2017
Mrs. McConaughy Geometry

10. Mrs. McConaughy Geometry
Homework
Homework: Transversals and Special Angles WS plus text: ________
4/26/2017
Mrs. McConaughy Geometry