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Question 320003
JEE Mathematics · Easy

Circle: Radius formula MCQ

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Radius formulaEasyQuestion 320003

Question

For the same circle x² + y² − 4x + 6y − 12 = 0, the radius is:
  1. A
    5
    Correct
  2. B
    4
  3. C
    √12
  4. D
    √13

Correct answer

5

Explanation

Radius = √(g² + f² − c) = √(4 + 9 − (−12)) = √(4 + 9 + 12) = √25 = 5.

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