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Chaitanya_1986
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Refer to the figure below,Chaitanya_1986 wrote:Please Help
OC is the radius of the circle.
Hence, AB = OC implies, AB = OC = OD = OB
Hence, triangle ABO is isosceles with AB = OB.
Hence, angle BAO = angle BOA = x (say)
Hence, angle ABO = (180 - 2x)
Now on straight line AC, angle ABO = (180 - 2x)
Hence, angle CBO = 180 - (180 - 2x) = 2x
Again triangle CBO is isosceles with OB = OC
Hence, angle BCO = CBO = 2x
Hence, angle BOC = (180 - 4x)
Now on straight line AD, (angle AOB + angle BOC + angle COD)= 180
Hence, (x + (180 - 4x) + angle COD) = 180
=> angle COD = 3x
Statement 1: angle COD = 3x = 60
Hence, angle BAO = x = 20; SUFFICIENT.
Statement 2: angle BCO = 2x = 40
Hence, angle BAO = x = 20; SUFFICIENT.
The correct answer is D.
