I is the incentre of ∆ ABC and if ∠BAC =70°,

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I is the incentre of ∆ ABC and if ∠BAC =70°, then ∠BIC is

1. 140°
2. 55°
3. 125°
4. 35°

Correct Option: C

As per the given in question , we draw a figure triangle ABC

BI and CI are bisectors of angles
∠B and ∠C.
Given , ∠BAC = 70°
∴ ∠ABC + ∠ACB = 180° – 70° = 110°
∴ 2∠IBC + 2 ∠ICB = 110°
⇒ ∠IBC + ∠ICB = 55°
∴ ∠BIC = 180° – 55° = 125°