find the area of a sector with a central angle of 185 degrees and a diameter of 6.4 mm. round to the nearest 10th.
a.66.1 m^2
b.5.3 m^2
c.16.5 m^2
d.21.0 m^2

Question

find the area of a sector with a central angle of 185 degrees and a diameter of 6.4 mm. round to the nearest 10th.
a.66.1 m^2
b.5.3 m^2
c.16.5 m^2
d.21.0 m^2

anonymous · Answer

to start up with, any idea how to find area of sector?

anonymous · Answer

that's what I need help with. I watched the lesson, but seriously don't understand.

anonymous · Answer

Ok. 

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Am pretty sure u can find the radius.


Actually area of circle is Pi x r^2, which is actually 360/360 x pi x r^2 since u cover whole circle.

However u cover only 185 degrees here.

So area of sector actually is - 185/360  x Pi x r^2.

(Generalising, area of sector = central angle x pi x r^2 / 360.)