Area of Segments and Annulus

Related Topics:
More Lessons for Grade 9 Math
Math Worksheets

Share this page to Google Classroom

Examples, solutions, videos, worksheets, games, and activities to help Geometry students learn how to find the area of segments and annulus.

The following diagram shows how to find the area of a segment when the angle is given in degrees or in radians. Scroll down the page for more examples and solutions for the area of sector, area of segment and area of annulus.
Area of Segment

Area of a Segment
The area of a segment in a circle is found by first calculating the area of the sector formed by the two radii and then subtracting the area of the triangle formed by the two radii and chord (or secant).
In segment problems, the most challenging aspect is often calculating the area of the triangle.

Area Of Sector And Segment Examples

Annulus Area
An annulus is similar to a ring or a castle’s moat; it is the area between two concentric circles. Calculating the annulus area, therefore, involves finding the difference of the two circles' area. A common trick on annulus problems is to give the distance between the small and large circle, and not the large circle’s radius.

Areas of Sectors, Segments, Annulus

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.
Mathway Calculator Widget

We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.