← 2.6 Area of a Part of a Circle
The chord and the isosceles triangle
Mathematics · Grade 10 · about 40 minutes
Two radii and a chord make an isosceles triangle; its area is half r squared sin theta, and the chord is 2 r sin(theta/2).
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- 7 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
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Other lessons in this sub-strand
- Arcs and sectors
- Segments and applications
- Area of an annulus
- Finding a missing radius of an annulus
- Minor and major sectors
- Perimeter of a sector
- Finding the angle or radius of a sector
- Area of an annular sector
- The chord and the isosceles triangle
- Minor and major segments in depth
- Common region of two intersecting circles
- Gardens, tracks, dartboards and paths