SOLUTION: Find the area of a segment of a circle if the diameter is 12 inches and the central angle is pi/4 radians?

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Question 34342: Find the area of a segment of a circle if the diameter is 12 inches and the central angle is pi/4 radians?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
First find out how much of the whole circle is %28pi%29%2F4radians.
There are 2%28pi%29radians in a complete circle, so you need to divide%28pi%29%2F4 by2%28pi%29
%28%28pi%29%2F4%29%2F%282%28pi%29%29+=+%281%2F8%29
The segment is 1%2F8 of the entire cicle, so the area of the segment will be 1%2F8 the area of the entire circle.
A+=+%28pi%29r%5E2 Butr+=+d%2F2 = 12%2F2+=+6
A+=+%28pi%29%286%5E2%29
A+=+%28pi%2936 This is the area of the entire circle. Divide by 8 the get the area of the segment.
A%2F8+=+36%28pi%29%2F8
A%2F8+=+%289%2F2%29%28pi%29
Area of the segment is:
A%28s%29+=+%289%2F2%29%28pi%29 Square inches.