SOLUTION: What is the area enclosed by a circular sector whose radius is r and arc length is s.

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Question 149138: What is the area enclosed by a circular sector whose radius is r and arc length is s.
Found 2 solutions by Earlsdon, edjones:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You could try proportions on this problem:
Let's compare the ratio of the arc length, S, to the circumference of the circle, C, with the ratio of the area enclosed by the sector A%5Bs%5D to the area of the entire circle A%5Bc%5D+=+%28pi%29r%5E2. Remember that C+=+2%28pi%29r
S%2FC+=+A%5Bs%5D%2FA%5Bc%5D
S%2F2%28pi%29r+=+A%5Bs%5D%2F%28pi%29r%5E2 Simplify and solve for A%5Bs%5D
S%28pi%29r%5E2%2F2%28pi%29r+=+A%5Bs%5D
A%5Bs%5D+=+Sr%2F2

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
pi*r^2=A (circle)
pi*2r=C (circle)
C/s=2pi radians/s [s is in radians]
A {circle}*(s/(2pi radians))=A {enclosed by the circular sector}
.
Ed