Can someone answer with steps and explanation? Thanks.

Step-by-step explanation:

Since Segment BOA is a diameter:

Arc Ac and Arc CB are in a ratio of two to four. Since Segment BOA is a diameter, Arc ACB measures 180°. Letting the unknown value be x, we can write that:

Hence:

Thus, Arc CB = 120°. By the Inscribed Angle Theorem:

Therefore, ΔABC is a 30-60-90 triangle. Its sides are in the ratios shown in the image below.

Since AC is opposite from the 30° triangle, let AC = a.

We are given that AC = 9. Hence, a = 9.

BC is opposite from the 60° angle and it is given by a√3. Therefore:

sine

step-by-step explanation:

b

step-by-step explanation:

it have 5 sides and 5 identicle angle.the rest does not have the same property as b.

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