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If mBC in circle A is 60°, what is mBDC?Α. 60°Β. 45°C. 30D. 25

If mBC in circle A is 60°, what is mBDC?Α. 60°Β. 45°C. 30D. 25-example-1
User Logu
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1 Answer

21 votes
21 votes
Answer:

measure of ∠BDC = 30° (option C)

Step-by-step explanation:

Given:

A circle with measure of arc BC = 60°

To find:

measure of ∠BDC

From the diagram, arc BC is common to m∠BAC and m∠BDC

This means the central angle of ∠BAC is the same as the central angle of ∠BDC

To find the angle of BDC, we will apply the theorem:

central angle = 2(inscribed angle)

The Central angle is represented by arc BC = 60°

inscribed angle = ∠BDC


\begin{gathered} 60\text{ = 2\lparen\angle BDC\rparen} \\ (60)/(2)\text{ = \angle BDC} \\ \\ ∠BDC=\text{ 30\degree \lparen option C\rparen} \end{gathered}

User Silas Reinagel
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