A quadrilateral ABCD is inscribed in a circle with centre O. If $$\angle$$BOC=92$$^\circ$$ and $$\angle$$ADC=112$$^\circ$$, then $$\angle$$ABO is equal to:
In $$\triangle\ $$OBC,
OC = OB
$$=$$> Â $$\angle$$OBC = $$\angle$$OCB
Let $$\angle$$OBC = $$\angle$$OCB = x
$$\angle$$OBC +Â $$\angle$$OCB +Â $$\angle$$BOC =Â 180$$^\circ$$
$$=$$>Â x + x +Â 92$$^\circ$$ =Â 180$$^\circ$$
$$=$$>Â 2x =Â 88$$^\circ$$
$$=$$>Â Â x =Â 44$$^\circ$$
$$=$$> Â $$\angle$$OBC = $$\angle$$OCB =Â 44$$^\circ$$
In cyclic quadrilateral ABCD, sum of opposite angles = 180$$^\circ$$
$$=$$> Â $$\angle$$ABC +Â $$\angle$$ADC =Â 180$$^\circ$$
$$=$$> Â $$\angle$$ABO + $$\angle$$OBC + $$\angle$$ADC = 180$$^\circ$$
$$=$$> Â $$\angle$$ABO +Â 44$$^\circ$$ +Â 112$$^\circ$$ =Â 180$$^\circ$$
$$=$$> Â $$\angle$$ABO +Â 156$$^\circ$$ =Â 180$$^\circ$$
$$=$$> Â $$\angle$$ABO =Â 24$$^\circ$$
Hence, the correct answer is Option A
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