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Circumcircle and Incircle of a Triangle
Last updated at May 31, 2026 by Teachoo
Circumcircle and Incircle of a Triangle
Class 9
Chapter 6 Class 9 - Measuring Space: Perimeter and Area (Ganita Manjar
- Definition (and Quesitons)
- Perimeter of Different Shapes
- Perimeter of a Circle - C/D Ratio
- Pi is Irrational
- Length of an Arc of a Circle
- Problems, Puzzles, and Paradoxes on Perimeter
- Exercise Set 6.1
- Area of Square & Rectangle
- Area of a Parallelogram
- Area of a Triangle
- Heron's Formula
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Circumcircle and Incircle of a Triangle
- Brahmagupta’s Formula for the Area of a Cyclic 4-gon
- Squaring a Rectangle
- Exercise Set 6.2
- Area of a circle
- Exercise Set 6.3
- End-of-Chapter Exercises
Transcript
Circumcircle and Incircle of a Triangle Let’s look into the definitions of both of them in detail Incircle The Incircle is the largest possible circle that can fit completely inside the triangle. It perfectly grazes (is tangent to) all three sides. Its center, the Incenter, is calculated precisely where all three Angle Bisectors (the dashed lines slicing the corners perfectly in half) meet. Notice how, no matter how crazy you drag the triangle, the incenter is always trapped safely inside! Circumcircle The Circumcircle is the perfect circle that wraps around and touches all three outside corners (vertices) of the triangle. Its center, the Circumcenter, is found exactly where the three Perpendicular Bisectors (the dashed lines cutting the triangle's edges perfectly in half at 90°) intersect.
