Proving Angle Relationships

Which justifies step 4?

• Vertical Angles Theorem

• Corresponding Angles Postulate

• Symmetric Property of Congruence

• Substitution Property of Congruence

Find m∠12 if m∠11 = 11x and m∠13 = 10x + 12. Then determine which theorem justifies your work.

• 92°, Supplement Theorem

• 92°, Vertical Angles Theorem

• 88°, Supplement Theorem

• 88°, Vertical Angles Theorem

The angle relationship shown is - 

• complementary angles

• supplementary angles

• vertical angles

• adjacent angles

• 20°

• 30°

• 40°

• 60°

angles supplementary to the same angle or to congruent angle are congruent

• congruent supplements

• congruent complements

• linear pair

• vertical

angles complementary to the same angle or to congruent angles are congruent

• congruent supplements

• complement

• vertical

• congruent complements

What is the justification?

• Reflexive Property of Congruence

• Vertical Angles Theorem

• Supplement Theorem

• Complement Theorem

What is the justification?

• Vertical Angles Theorem

• Transitive Property of Equality

• Compliment Theorem

• Reflexive Property of Congruence

What is the justification?

• Congruent Complements Theorem

• Definition of Perpendicular

• Definition of a Right Angle

• Definition of Complementary Angles