Footnote 0.2.

However, note that in the case of the Pythagorean Theorem, it is also the case that if \(a^2 + b^2 = c^2\text{,}\) then \(a\) and \(b\) are the legs of a right triangle with hypotenuse \(c\text{.}\) So we could have also expressed this theorem as a biconditional: “\(a\) and \(b\) are the legs of a right triangle with hypotenuse \(c\) if and only if \(a^2 + b^2 = c^2\text{.}\)
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