A,B and C are the 3 points on the circle and O is the centre of the circle.If <OAB is 40°, <ABC is 120°,<BCO is y° and <COA is x°. Find the value of x° and y°?

1 Answer
Feb 16, 2018

y=80°˛ x=120°!

Explanation:

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OA=OB=OC=r
∠ OAB=∠ ABO=40°
∠OBC=120°-40°=80°
y°=∠ BCO=∠ OBC=80°
∠COB=180°-2 \cdot 80°=20°
∠BOA=180°-2 \cdot 40°=100°
x°=∠COB+∠BOA=120°