Beginning Proofs

If M is the midpoint of AB, then AM = MB

• Addition POE
• Def. of Midpoint 
• Reflexive POE
• Symmetric

Tags

CCSS.HSG.GPE.B.6

If A = B, then 8A = 8B

• Multiplication POE
• Division POE
• Reflexive POE
• Addition POE

Tags

CCSS.HSA.REI.A.1

CCSS.HSA.REI.B.3

If <1 and <2 are complementary, then m<1 + m<2 = 90

• Addition POE
• Subtraction POE
• Def of right angle
• Def of Complementary Angles

Tags

CCSS.7.G.B.5

IF <ABC ≅ <DEF, then m<ABC = m<DEF

• Reflexive POE
• Addition POE
• Def. of congruent angles
• Def. of right angles

Tags

CCSS.HSG.CO.B.7

If X = Y, then X + 5 = Y + 5

• Addition POE
• Subtraction POE
• Reflexive POE
• Transitive POE

Tags

CCSS.HSA.REI.A.1

CCSS.HSA.REI.B.3

If X is between R & T on a line,
then RX + XT = RT

• Addition POE
• Substitution POE
• Angle Addition Post.
• Segment Addition Post.

Tags

CCSS.HSG.SRT.B.4

What is the reason?

• Definition of Complementary
• Definition of 180 
• Definition of supplementary
• Angle Addition

Tags

CCSS.7.G.B.5

What is the reason?

• Definition of complementary

• Definition of supplementary

Tags

CCSS.7.G.B.5

Which justifies the next step?

• Definition of linear pair
• Definition of supplementary angles
• Congruent supplements thm
• Linear pair postulate

Tags

CCSS.HSG.CO.C.9

Which justifies the next step?

• Segment addition postulate
• Definition of an angle bisector
• Angle addition postulate
• Definition of right angles

Tags

CCSS.HSG.CO.C.9