Exploring Proofs of Lines and Angles

What is the structure of a proof in this worksheet?

• Three columns with statements, reasons, and diagrams

• Four columns with statements, reasons, diagrams, and conclusions

• Two columns with statements and reasons

• One column with statements only

What is the first reason always given in a proof?

• Definition of perpendicular

• Substitution

• Definition of complementary

• Given

What do complementary angles add up to?

• 180 degrees

• 45 degrees

• 90 degrees

• 360 degrees

In the second proof problem, what do linear pairs add up to?

• 45 degrees

• 90 degrees

• 180 degrees

• 360 degrees

What method is used to show that two angles are equal in the second proof problem?

• Substitution

• Addition

• Division

• Multiplication

What do supplementary angles add up to?

• 45 degrees

• 360 degrees

• 180 degrees

• 90 degrees

In the third proof problem, what is the goal of the proof?

• To show that two angles are complementary

• To show that two angles are equal

• To show that two angles are supplementary

• To show that two angles are congruent

What type of angles are across an intersection?

• Corresponding angles

• Supplementary angles

• Vertical angles

• Complementary angles

What is the reasoning used to prove that corresponding angles are congruent?

• Definition of perpendicular

• Definition of complementary

• Definition of a linear pair

• Definition of corresponding angles

What is the final step to prove that two angles are supplementary in the sixth proof problem?

• Division

• Addition

• Multiplication

• Substitution