﻿ If common chord of the circle C with centre at (2, 1) and radius r and the circle x2 + y2 – 2x – 6y + 6 = 0 is a diameter of the second circle, then the value of r is   : Kaysons Education

# If Common Chord Of The Circle C with Centre At (2, 1) And Radius r and The Circle x2 + y2 – 2x – 6y + 6 = 0 Is A Diameter Of The Second Circle, Then The Value Of r is

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## Question

### Solution

Correct option is

3

Equation of the circle C is

(x – 2)2 + (y – 1)2 = r2

⇒        x2 + y2 – 4x – 2y + 5 – r2 = 0

Equation of the common chord is

If it is a diameter of the second circle, it passes through the centre (1, 3) of the circle

#### SIMILAR QUESTIONS

Q1

A line meets the coordinate axes in A and B. A circle is circumscribed about the triangle OAB. If m and n are the distances of the tangent to the circle at the origin from the points A and B respectively, the diameter of the circle is

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x2 + y2 – 4x + 2y + 4 = 0 orthogonally, is

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Q7

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