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Can you please help me, I got some of it wrong but not sure what

Can you please help me, I got some of it wrong but not sure what-example-1
User Ilansas
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1 Answer

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It is required to find the area of the sector AOB in terms of π.

Notice that the central angle is 120º.

Recall that the Area of a sector is given as:


A=(\theta)/(360^(\circ))*\pi r^2

Where θ is the central angle and r is the radius.

Substitute θ=120º and r=9 into the formula:


\begin{gathered} A=(120^(\circ))/(360^(\circ))*\pi(9^2) \\ \end{gathered}

Evaluate the expression on the right:


A=\frac{\cancel{120^(\circ)}1}{\cancel{360^(\circ)}3}*81\pi=(1)/(3)*81\pi=27\pi\text{ square units}

Hence, the required area of the sector in terms of π is 27π.

User Nguyen Tran
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