AB is a chord in a circle with centre O. AB is produced to C such that BC is equal to the radius of the circle. C is joined to O and produced to meet the circle at D. If $$\angle ACD = 32^\circ$$, then the measure of $$\angle AOD$$ is .........
BC = OB (Given)
$$\angle BCO = \angle BOC = 32\degree =Â \angle ACD$$
$$\angle OBC = 180 -Â \angle BCO - \angle BOC$$ = 180 - 32 - 32 = 116
$$\angle BOD =Â \angle OBC +Â \angle OCB$$ = 116 +Â 32 = 148
In triangle AOB -Â
$$\angle ABO = 180 -Â \angle$$ OBC = 180 - 116 = 64
$$\angle ABO = \angle OA$$ = 64Â
($$\because$$OA = OB)
$$\angle AOB = 180 -Â \angle ABO - \angle$$ OAB = 180 - 64 -64 = 52
$$\angle AOD =Â \angle BOD -Â \angle AOB = 148 - 52 = 96\degree$$
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