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In a $$\triangle$$ABC,the bisectors of $$\angle$$B and $$\angle$$C meet at O with in the triangle. If $$\angle$$A = 110$$^\circ$$, then the measure of $$\angle$$BOC is:
From the figure,
OB and OC are angular bisectors of $$\angle$$B and $$\angle$$C
$$=$$> $$\angle$$OBC = $$\frac{\angle \text{B}}{2}$$ and $$\angle$$OCB = $$\frac{\angle \text{C}}{2}$$
In $$\triangle$$ABC,
$$\angle$$A + $$\angle$$B + $$\angle$$C = 180$$^{\circ\ }$$
$$=$$> 110$$^{\circ\ }$$ + $$\angle$$B + $$\angle$$C = 180$$^{\circ\ }$$
$$=$$> $$\angle$$B + $$\angle$$C = 180$$^{\circ\ }$$ - 110$$^{\circ\ }$$
$$=$$> $$\angle$$B + $$\angle$$C = 70$$^{\circ\ }$$ ......................(1)
In $$\triangle$$OBC,
$$\angle$$BOC + $$\angle$$OBC + $$\angle$$OCB = 180$$^{\circ\ }$$
$$=$$> $$\angle$$BOC + $$\frac{\angle \text{B}}{2}$$ + $$\frac{\angle \text{C}}{2}$$ = 180$$^{\circ\ }$$
$$=$$> $$\angle$$BOC + $$\frac{\angle \text{B}+\angle \text{C}}{2}$$ = 180$$^{\circ\ }$$
$$=$$> $$\angle$$BOC + $$\frac{70^{\circ\ }}{2}$$ = 180$$^{\circ\ }$$
$$=$$> $$\angle$$BOC = 180$$^{\circ\ }$$- 35$$^{\circ\ }$$
$$=$$> $$\angle$$BOC = 145$$^{\circ\ }$$
Hence, the correct answer is Option C
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