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Can someone help me with this geometry question?/ the second answer is 34.92,82.90,57.86

Can someone help me with this geometry question?/ the second answer is 34.92,82.90,57.86-example-1
User SashaQbl
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1 Answer

5 votes

Given:

The length of the arc PQ=12 cm

The angle of the sector POQ is 60 degrees.

To find the area of the sector and perimeter of the sector:

Using the length of an arc formula,


\begin{gathered} l=(\theta)/(360)*2\pi r \\ 12=(60)/(360)*2*(22)/(7)* r \\ 12=(22)/(21)* r \\ r=(12*21)/(22) \\ r\approx11.455\operatorname{cm} \end{gathered}

Using the formula of area of the sector,


\begin{gathered} A=(\theta)/(360)*\pi r^2 \\ =(60)/(360)*(22)/(7)*(11.455)^2 \\ =68.76\operatorname{cm} \end{gathered}

Therefore, the area of the sector is approximately 68.76 square cm.

Using the formula of the perimeter of the sector,


\begin{gathered} P=2r+l \\ =2(11.455)+12 \\ =22.91+12 \\ =34.91 \end{gathered}

Therefore, the perimeter of the sector is approximately 34.91 cm.

User JustinN
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