Nomor 1-2 tolong dibantu dong

Nomor 1-2 tolong dibantu dong

1. Tali busur (A)

2.
$OC = sqrt{ {r}^{2} - {BC }^{2} } \ OC = sqrt{ {17}^{2} - {8}^{2} } \OC = sqrt{ 289 - 64 } \ OC = sqrt{225 } \ OC = 15 : cm::(B)$

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