411 REFERENCE · Wikibooks
Geometry/Appendix B
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Section 2.3 - Using Proofs in Geometry
1.
Angle 2 = 120 degrees since it is supplementary to angle 1. Supplementary angles are any two angles whose sum is 180 degrees.
Angle 3 = 60 degrees since
Angle 1 and Angle 3 are vertical angles. Vertical angles are two nonadjacent angles formed by two intersecting lines.
Angle 4 = 120 degrees since it is supplementary to angle 1.
Angle 5 = angle 1 by the Transversal Postulate.
Angle 6 = angle 2, angle 7 = angle 3, and angle 8 = angle 4 by the Transversal Postulate.
2.
Angle 2 = angle 3 is given
Lines R and S are parallel by the Alternate Interior Angles Converse Postulate
Chapter 5
Section 5.1 - Methods of Proving that Triangles are Congruent
1. Yes; triangle RUN = triangle DIH by ASA
2. No; the sides and angles do not match
3. Yes; triangle SUM = triangle HRC by ASA
4. Yes; triangle QWE = triangle TYR by SSS