Answer:
See below.
Explanation:
Rectangle - c = √a²+b² = √6²+12² = 13.41641, or 13.42
Square - c = √a²+b² = √6²+6² = 8.48528, or 8.49
He is incorrect. 13.42 halved is 6.71, not 8.49.
-hope it helps
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