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Question
The bisectors of angles A and B of a scalene triangle ABC meet at O.
- What is the point O called?
- OR and OQ are drawn perpendicular to AB and CA respectively. What is the relation between OR and OQ?
- What is the relation between angle ACO and angle BCO?
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Solution
- O is called the incentre of the incircle of ΔABC.
- OR and OQ are the radii of the incircle and OR = OQ.
- OC is the bisector of angle C.
∴ ∠ACO = ∠BCO
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