In ΔABC, ∠B = 70°and ∠C = 60°. The internal bisectors of the two smallest angles of ΔABC meet at O. The angle so formed at O is
Given : In ΔABC, ∠B = 70°and ∠C = 60°
=> $$\angle A = 180^\circ-70^\circ-60^\circ=50^\circ$$
Thus, the two smallest angles are ∠A and ∠C
To find : $$\angle AOC = \theta$$ = ?
Solution : AO and OC are angle bisectors.
=> $$\angle OAC = \frac{\angle A}{2}=\frac{50}{2}=25^\circ$$
Similarly, $$\angle OCA=30^\circ$$
In $$\triangle$$ AOC
=> $$\angle$$ OAC + $$\angle$$ OCA + $$\angle$$ AOC = $$180^\circ$$
=> $$25^\circ+30^\circ+\theta=180^\circ$$
=> $$\theta=180-55=125^\circ$$
=> Ans - (A)
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