We are given the following statement: The universe is all integers. If a-3b is even, then a+b is even. I began off with saying that 3 cases exist: a is odd and b is even, a is even and b is odd, both a and b are odd, and both a and b are even. After this point I got really confused and lost. Can someone please point me in the right direction?(adsbygoogle = window.adsbygoogle || []).push({});

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# Tricky Mathematical Proof

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