Geometry Explorer
Exterior Angle Theorem • Class 9
Theorem Statement
"The exterior angle of a triangle is equal to the sum of the two opposite interior angles."
Live Calculations
Theoretical Proof
Step 1: Triangle Property
∠A + ∠B + ∠ACB = 180°
Step 2: Linear Pair
∠ACB + ∠ACD = 180°
Step 3: Conclusion
∠ACD = ∠A + ∠B
Observation Log
| No. | ∠A+∠B | ∠ACD | Result |
|---|
Concept Challenge
Designed by Govinda Paudel, Sky Rider School, Chitwan









