Q14 of 34 Page 170

In a triangle, each of the bigger angles is twice the third angle. Find the angles.

In a triangle ABC, let ∠C be the third angle and ∠A and ∠B be the bigger ones. It is given that


∠A = ∠B = 2∠C


We know that the sum of the angles of a triangle is 180°.


⇒ 2∠C + 2∠C + ∠C = 180°


⇒ 5∠C = 180 °


⇒ ∠C = 36°


So, ∠B = ∠A = 2× ∠C = 72°


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