Ask your own question, for FREE!
Mathematics 10 Online
OpenStudy (anonymous):

Find the area of the shaded sections.

OpenStudy (anonymous):

OpenStudy (mathstudent55):

Do you know the formula for the area of a sector of a circle?

OpenStudy (mathstudent55):

|dw:1376935514806:dw|

OpenStudy (jdoe0001):

area of a circle => \(\bf \Large \pi r^2\) area of a sector of a circle => \(\bf \Large \cfrac{\theta r^2 \pi }{360}\)

OpenStudy (anonymous):

I believe it is\[\frac{ n }{ 360 }\times2\times(\frac{ 22 }{ 7 })\times(r)\]

OpenStudy (mathstudent55):

\(\large {A_{sector} = \dfrac{n^o}{360^o} \pi r^2 }\)

OpenStudy (anonymous):

yes that is correct

OpenStudy (mathstudent55):

Good. Now on to your problem. You cna think of it as two sectors. Can you find the central angle of each one?

OpenStudy (anonymous):

120 degrees. right?

OpenStudy (anonymous):

I think I found the are of the triangle

OpenStudy (mathstudent55):

|dw:1376935712415:dw|

OpenStudy (anonymous):

I mean 8 times pi

OpenStudy (anonymous):

nevermind. I thought the picture I posted said the angle of the shaded region was 120 degrees

OpenStudy (anonymous):

i need to rework the problem

OpenStudy (mathstudent55):

Each shaded sector has a central angle of 60 degrees. \(\large {A_{sector} = \dfrac{n^o}{360^o} \pi r^2 }\) The area of one shaded sector is: \(\large {A_{sector} = \dfrac{60^o}{360^o} \pi 4^2 }\) \(\large {A_{sector} = \dfrac{1}{6} \pi (16) }\) \(\large {A_{sector} = \dfrac{16}{6} \pi }\) \(\large {A_{sector} = \dfrac{8 \pi}{3}}\) The area of both shaded sectors is \(\large {A = 2 \times\dfrac{8 \pi}{3}}\) \(\large {A = \dfrac{16 \pi}{3}}\)

OpenStudy (mathstudent55):

|dw:1376936062306:dw|

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!