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Daily Warm-Up. Daily Warm-Up. Given : m 1 = m 3 Prove : m 1 + m 2 = m 2 + m 3. Reasoning in Algebra. During this lesson, you will write simple algebraic proofs using angle and segment addition postulates. Recall : Angle Addition Postulate.
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Daily Warm-Up Geometry
Daily Warm-Up Given: m 1 = m 3 Prove: m 1 + m 2 = m 2 + m 3 Geometry
Reasoning in Algebra During this lesson, you will write simple algebraic proofs using angle and segment addition postulates. Geometry
Recall: Angle Addition Postulate If D is in the interior of ∠ ABC, then _____________________. A D B C Geometry
Recall: Segment Addition Postulate If M is between collinear points A and Y, then ______________. AM + MY = AY Y M A Geometry
Example 1 Given: m ∠ DOF = 124, m ∠ DOE = 36. Find m ∠ EOF. O D E F Geometry
Labeling Angles Using Numbers C D B ∠ 1 = _____ ∠ 2 = _____ ∠ 3 = _____ A 2 3 1 O Geometry
Reflexive Property of Congruence A A and AB AB for any angle A and any segment AB. You will use the reflexive property in many proofs. Geometry
Example 2: Writing a Simple Proof Given: m ∠ 1 = m ∠ 3 Prove: m ∠ WOY = m ∠ ZOX Z Y X 3 2 W 1 Geometry
Example 3: Writing a Simple Proof Given: AB = CD Prove: AC = BD D C B A Geometry
Homework Assignment Supplemental WS: Angle and Segment Addition 1-17 all. Geometry