Discussion
Find the radius of the circle whose center is at (3, 2) and which passes through the point (-5, 6).
Answer: A
Correct answer: \(\sqrt{80}\)
The radius is the distance from the centre to any point on the circle, so apply the distance formula to (3, 2) and (-5, 6).
\[r = \sqrt{(-5-3)^2 + (6-2)^2} = \sqrt{(-8)^2 + 4^2} = \sqrt{64+16} = \sqrt{80}\]
This simplifies to \(4\sqrt{5} \approx 8.94\), which is why neither 8 nor 10 is correct - the radius falls between them.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development