Published by:
CGP EDU Academic Team
Published on: August 14, 2026
In Δ ABC , P is an interior point such that ∠ PAB = 10º ∠ PBA = 20º, ∠ PCA = 30º, ∠ PAC = 40º then prove that Δ ABC is isosceles
Text Solution
Verified by ExpertsThe correct answer is:
CHECK THE SOLUTION.
From Δ APB, Δ PBC and Δ PCA , using sine rule
= 
= 
= 
= 
⇒ sin30º . sinx.sin10º = sin20º.sin(80º – x) sin40º
⇒ x = 60º
∴ ∠ BCA = ∠ CAB = 50º
So, Δ ABC is an isosceles triangle.
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