[Proof by Contrapositive] Let m, n∈ Z. Prove that if m2 + n2 is odd, then either m or n is even.

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What properties allow transformation to be used as a problem solving tool

Satchi found a used bookstore that sells pre-owned dvds and cds. dvds cost $9 each, and cds cost $7 each. satchi can spend no more than $45.

What is the similarity ratio of a cube with volume 729m^3 to a cube with volume 3375 m^3