Basic Geometry and Proofs

Q1. What is the angle of a right triangle?

• A) 100°

• B) 80°

• C) 90°

• D) 180°

Q1. What is the angle of a right triangle?

• A) 100°

• B) 80°

• C) 90°

• D) 180°

Which are pairs of vertical angles?

• ∠COB & ∠COA

• ∠AOD & ∠AOC

• ∠COB & ∠AOD

• ∠BOD & ∠AOD

If LN = 32, what is MN?

• 11

• 20

• 12

• 10

How can you prove step #2?

• Vertical angle theorem

• Subtraction property of equality

• Transitive property of congruence

• Definition of supplementary angles

What reason justifies statement #2?

• Definition of Midpoint

• Transitive Property

• Addition Property

• Segment Addition Postulate

• Substitution Property

How can you prove step #5?

• Vertical angle theorem

• Subtraction property of equality

• Transitive property of congruence

• Definition of supplementary angles

Identify the  missing statement or reason

• Given

• Vertical Angles Theorem

• Definition of Angle Bisector

• Alternate Interior Angles Theorem

How can you prove step #4?

• Vertical angle theorem

• Subtraction property of equality

• Transitive property of congruence

• Definition of supplementary angles

What is the "reason" for step 5 of the proof?

• Angle Bisector Theorem

• Reflexive property

• CPCTC Theorem

• Proof