Same chapter3 marksDifficulty: Medium
Find the equation of the circle with the points (1, 2) and (5, 6) as the ends of a diameter.
Circles
3 marksDifficulty: Medium
Find the centre and radius of the circle x2 + y2 − 6x + 4y − 12 = 0.
Original Khojo Papers practice question — not from a past board paper.
Answer
Centre (3, −2) and radius 5
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Comparing with x2 + y2 + 2gx + 2fy + c = 0 gives g = −3, f = 2 and c = −12, so the centre is (3, −2) and the radius is √(9 + 4 + 12) = 5.
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