The angle bisectors of triangle ABC converge at the incenter I. Given that the measure of ∠BIC is 125°, what is the measure of ∠BAC?
70°
For any triangle ABC with incenter I (where the internal angle bisectors meet), the angle subtended at I by side BC satisfies the standard identity:
\(\angle BIC = 90^{\circ} + \dfrac{\angle BAC}{2}\)
Apply with \(\angle BIC = 125^{\circ}\):
\(125^{\circ} = 90^{\circ} + \dfrac{\angle BAC}{2}\)
\(\dfrac{\angle BAC}{2} = 35^{\circ} \quad \Rightarrow \quad \angle BAC = 70^{\circ}\)
Hence, the answer is option B.
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