Circles
The length of tangent from point (5, 4) to circle x² + y² = 9 is
Select the correct option:
Solution
√32
- Formula: The length of a tangent L from an external point (x1,y1) to circle x2+y2−r2=0 is L=x12+y12−r2.
- Identify Data: Point is (5,4), Circle is x2+y2−9=0 (r2=9).
- Calculate Power of Point:
- S1=52+42−9=25+16−9=32.
- Extract Length:
- L=32=42.
🔒 Solution Hidden from View
Submit your answer to unlock the detailed step-by-step solution.
More circles Practice Questions
From the external point (5, 1) a tangent is drawn to the circle x^2 + y^2 = 9; what is the length of...
From the external point (5, 1) a tangent is drawn to the circle x^2 + y^2 = 9; what is the length of...
Two circles given by x^2 + y^2 = 9 and x^2 + y^2 - 6x + 5 = 0 intersect; what is the equation of the...
Two circles given by x^2 + y^2 = 9 and x^2 + y^2 - 6x + 5 = 0 intersect; what is the equation of the...
Consider the circle described by x^2 + y^2 - 6x + 8y - 11 = 0; what are the coordinates of its centr...
Consider the circle described by x^2 + y^2 - 6x + 8y - 11 = 0; what are the coordinates of its centr...
A line y = mx + 4 is tangent to the circle x^2 + y^2 = 4; what is the value of the slope m that make...
A line y = mx + 4 is tangent to the circle x^2 + y^2 = 4; what is the value of the slope m that make...
The radius of the circle x² + y² - 6x + 4y - 12 = 0 is
The radius of the circle x² + y² - 6x + 4y - 12 = 0 is
About This Question
- Subject
- mathematics
- Chapter
- coordinate geometry
- Topic
- circles
- Difficulty
- Hard
- Year
- 2025
Solution
Correct Answer:
√32
- Formula: The length of a tangent L from an external point (x1,y1) to circle x2+y2−r2=0 is L=x12+y12−r2.
- Identify Data: Point is (5,4), Circle is x2+y2−9=0 (r2=9).
- Calculate Power of Point:
- S1=52+42−9=25+16−9=32.
- Extract Length:
- L=32=42.
This hard difficulty mathematics question is from the chapter coordinate geometry, covering the topic of circles. It appeared in the 2025 exam.
Looking for more practice? Explore all mathematics questions or browse coordinate geometry questions on RankGuru.