Circle annulus

There are two concentric circles in the figure. The chord of the larger circle, 10 cm long, is tangent to the smaller circle. What does annulus have?

Correct answer:

S =  78.5398 cm2

Step-by-step explanation:

t=10 cm R2 = (t/2)2+r2 R2r2 = (t/2)2 S = π   R2  π   r2 S = π   (R2r2)  S=π (t/2)2=3.1416 (10/2)2=78.5398 cm2

Did you find an error or inaccuracy? Feel free to write us. Thank you!

Tips for related online calculators
See also our right triangle calculator.
See also our trigonometric triangle calculator.

We encourage you to watch this tutorial video on this math problem: video1   video2

Related math problems and questions: