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google search
Google search results:
1: https://www.student.uwa.edu.au/__data/assets/pdf_file/0005/1861052/LogicAndProo-Solutions132.pdf
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2: https://cs.stanford.edu/~jtysu/proofs.pdf
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3: https://gmatclub.com/forum/if-y-is-an-even-integer-and-x-is-an-odd-integer-which-of-the-followin-242522.html
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4: https://www.varsitytutors.com/psat_math-help/integers/arithmetic/even-odd-numbers?page=3
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5: https://faculty.math.illinois.edu/~hildebr/347.summer19/even-odd-proofs-sol.pdf
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6: https://www.theguardian.com/notesandqueries/query/0,5753,-2212,00.html
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7: https://math.stackexchange.com/questions/3388813/the-sum-of-an-even-integer-and-an-odd-integer-is-always-odd-direct-proof
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8: https://quizlet.com/37275346/arithmetic-flash-cards/
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