Geometry Proofs Vocabulary

When trying to prove two angles are supplementary, what must you show in your proof?

• that the angles are equal

• that the angles add up to 180 degrees

• that the angles are a linear pair

• that the angles are right angles

m<AMX + m<XMB = m<AMB

• Segment addition postulate

• Angle addition postulate

• Definition of supplementary angles

• Definition of angle bisector

What should you conclude by definition of perpendicular?

• <ORP is a right angle

• QR + RP = QP

• <ORQ and <ORP are complementary

Given: <1 and <3 are vertical angles. What should you conclude by the vertical angles theorem?

• <1 and <2 are a linear pair

• <1 and <3 are right angles

• <2 and <4 are vertical angles

Given: <1 and <2 are a linear pair. Conclusion: m<1 + m<2 = 180. What is the reason that allows you to draw that conclusion?

• Angle addition postulate

• Definition of straight angle

• Linear Pair Postulate

• Definition of supplementary

Given: AB is the segment bisector of PQ. What conclusion can you draw?

• PF = QF

• F is the midpoint of PQ

• m<PFA = m<QFA

• <PFQ is a straight angle

Which of the following CAN you conclude from the diagram?

• lines l and m are perpendicular

• <a and <b are adjacent

• <a and <b are complementary

• m<a = m<b

Given: ∠1 and ∠3 are vertical angles. What should you conclude by the vertical angles theorem?

•  $\angle1$  and $\angle3$  are right angles.

What does it mean to bisect a segment or an angle?

• Split it into 3 equal parts.

• Split it into 2 equal parts.

• Split into 4 equal parts.

• Double it.

In the given proof, what are the reasons for step 1 and 2?

• Angles that form a linear pair are supplementary.

• Substitution

• Reflexive Property of Congruence

• Angles of equal measure are congruent.