Chapter 2.5 Proving Angles Congruent

Bell Work• If you get an A, then you’ll get money

• 1) Amanda got a 95% in science– Conclusion:

• 2) Amanda got $100 from grandma– Conclusion:

• 3) If you are fit, then you are hot• If you are hot, then you will get a lot of dates– Conclusion:

Vocabulary

• Complementary Angle = two angles that add up to 90 (right angle)

• Supplementary Angle = two angles that add up to 180 (straight line)

• Theorem = A theorem is a conjecture that is proven

Vocabulary

• Paragraph proof = Proof written in paragraph form

Vertical Angles Theorem

• Vertical angles are congruent

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Example

• Which are vertical angles?

Congruent Supplements Theorem

• If two angles are supplements of the same angle (or of congruent angles), then the two angles are congruent

Congruent Complements Theorem

• If two angles are complements of the same angle (or of congruent angles), then the two angles are congruent

• All right angles are congruent• If two angles are congruent and

supplementary, then each is a right angle

Solving Example with Vertical Angles

Solving Example with Supplementary Angle

Solving Example with Complementary Angle

Solving problem with combination of vertical and supplementary

Activity (5 min)

• Write the summary about this section in your Cornell note.

• Some questions to consider:– What is the topic about?– What did I learn from this lesson?– What questions do I have?– How does it relate to other lessons/real life?

Classwork

• P 112 #1-6, 12, 13, 30-32