I need to determine the measure in degrees of arc BC??
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ANSWER:
120°
STEP-BY-STEP EXPLANATION:
We must calculate the area of the circle, using the following formula:
[tex]\begin{gathered} A=\pi\cdot r^2 \\ \text{ replacing} \\ A=\pi\cdot9^2 \\ A=81\pi \end{gathered}[/tex]We know that this area represents 360 °, we know the area of ABC, therefore we can calculate the amount in degrees that it represents in the following way:
[tex]\begin{gathered} \frac{360}{81\pi}=\frac{x}{27\pi} \\ x=\frac{360\cdot27\pi}{81\pi} \\ x=120 \end{gathered}[/tex]Therefore, the value of arc BC is equal to the angle of area ABC, that is, the arc of BC is equal to 120°