2'6 Algebraic Proof

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2.6 Algebraic Proof
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Props of Equality

• 1. Reflexive (reflex)
• Hint
• 2. Symmetric (symm)
• Hint
• 3. Transitive (trans)
• Hint

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Props of Equality

• 4. Addition (add)
• Hint
• 5. Subtraction (subtr)
• Hint
• 6. Multiplication (mult)
• Hint

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Props of Equality

• 7. Division (div)
• Hint
• 8. Substitution (subst)
• Hint
• 9. Distributive (distr)
• Hint

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Example Name the prop used

• If 3x 120 ? x 40.
• If 12 AB ? AB 12.
• If AB BC BC CD ? AB CD.
• If y 75 y mltA ? mltA 75.

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Paragraph Proof (review) informal proof in form
of paragraph that uses facts to justify each
step2-Column Proof formal proof in which 2
columns are needed 1. statements 2. reasons
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Parts of 2-Column Proof

• Given
• Prove

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Example 6-2a
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Example 6-2c
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Example 6-2e
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Example 6-4b
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Example 6-4c
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Assignment

• 2.6 p. 97 (14-25 all, 26-32 even, 38-42 even,
  48-52 even)