SOLUTION: 1. W ⊃ Z 2. W v Z / ∴ Z

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Question 1209011: 1. W ⊃ Z
2. W v Z / ∴ Z
Found 2 solutions by mccravyedwin, math_tutor2020:
Answer by mccravyedwin(407) About Me  (Show Source):
You can put this solution on YOUR website!
1. W  ⊃ Z
2. W  v Z  / ∴    Z

                |3.  ~Z      assumption for indirect proof
                |4.  Z v W       2, commutation
                |5.  W         4,3, disjunctive syllogism
                |6.  Z         1,5, modus ponens    
                |7. Z & ~Z     6,3, conjunction 
8. Z      lines 3-7 for indirect proof

Edwin

Answer by math_tutor2020(3816) About Me  (Show Source):
You can put this solution on YOUR website!

I'll use an arrow instead of a horseshoe symbol.
NumberStatementLine(s) UsedReason
1W --> Z
2W v Z
:.Z
3Z v W2Commutation
4~(~Z) v W3Double Negation
5~Z --> W4Material Implication
6~Z --> Z5, 1Hypothetical Syllogism
7~(~Z) v Z6Material Implication
8Z v Z7Double Negation
9Z8Tautology

Here's a list of rules of inference and replacement