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Simple Proofs & Theorems 1 and 2 Geometry 1.4. Definition : Postulates are statements that are assumed true. They are not proved to be true. Definition : Theorems are statements that are proved true using postulates and/or theorems that have already been proved .
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Simple Proofs & Theorems 1 and 2 Geometry 1.4
Definition: Postulates are statements that are assumed true. They are not proved to be true. Definition: Theorems are statements that are proved true using postulates and/or theorems that have already been proved. Two Types of Statements:Postulates & Theorems
Theorem 1: If two angles are right angles, then they are congruent. Theorem 2: If two angles are straight angles, then they are congruent.
Theorem 1: If two angles are right angles, then they are congruent. How to prove a theorem: 1. Rewrite the “IF – THEN” statement as “Given” and “Prove” 2. Draw a diagram with labels for all referenced objects 3. Write a “Two-Column” Proof
Theorem 2: If two angles are straight angles, then they are congruent. How to prove a theorem: 1. Rewrite the “IF – THEN” statement as “Given” and “Prove” 2. Draw a diagram with labels for all referenced objects 3. Write a “Two-Column” Proof
Example of (Very) Simple Two Column Proof: Given: <A and <B are right angles Prove: 1. 2.
Example of (Very) Simple Two Column Proof: Given: m<BAC=30 and m<DAC=30 Prove: 1. 2.