Same chapter3 marksDifficulty: Medium
Why can a tangent not be constructed from a point inside a circle?
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3 marksDifficulty: Medium
Explain why the circumcentre of an obtuse-angled triangle lies outside the triangle.
Original Khojo Papers practice question — not from a past board paper.
Answer
The circumcentre is where the perpendicular bisectors of the sides meet. In an obtuse-angled triangle the longest side subtends an obtuse angle, and the centre of the circle through the three vertices must lie on the far side of that longest side from the opposite vertex, which puts it outside the triangle.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
For a right-angled triangle the circumcentre lies exactly at the midpoint of the hypotenuse.
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