Question

AB и CD - хорды, CK=KD, AK=12, KB=3. Найти CD​

Answer 1

$CK*KD = AK*KB\\CK = KD\\CK^2 = AK*KB = 12 * 3 = 36 => CK = \sqrt{36} = 6\\CD = CK + KD = 2 CK = 2 * 6 = 12.\\Answer: 12$