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Question
The vertices of a triangle are O (0, 0), A (a, 0) and B (0, b). Write the coordinates of its circumcentre.
Solution
The coordinates of circumcentre of a triangle are the intersection of perpendicular bisectors of any two sides of the triangle.
Thus, the coordinates of circumcentre of triangle OAB are \[\left( \frac{a}{2}, \frac{b}{2} \right)\], as shown in the figure.
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