Help with indirect logic proof please

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    Logic Proof
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The discussion centers on proving the implication p→q using five axioms: A1: p→~y, A2: ~r→q, A3: p→~z, A4: x→q or z, and A5: r→x or y. The participants confirm that taking the contrapositive of certain axioms is essential for progressing with the proof. Specifically, the contrapositive of A5 leads to the conclusion that if both ~x and ~y are true, then ~r must also be true, which in turn allows for the derivation of q from A2. The logical flow is established through a series of justified steps based on the axioms provided.

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Using the five axioms below prove: p→q

A1: p→~y
A2: ~r→q
A3: p→~z
A4: x→ q or z
A5: r→x or y

Do I have to take the contrapositive of some of the axioms to begin this proof?
 
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Yes, that would be the simplest thing to do. The very first "axiom" gives you p-> ~y but there is no "~y-> " so you cannot continue directly. However, you do have "A5: r->x or y which has contrapositive ~(x or y)= (~x) and (~y)->~r and then both "A2: ~r-> q" and "A4: x-> q or z".
 
Am I on the right track with this?

Conclusions Justifications
1. p Given
2. ~z or ~y All cases
3. ~z Case 1
4. ~x A4
5. ~r A5
6. q A2
 

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