﻿ Find the radical centre of the circles, x2 + y2 + 3x + 2y + 1 = 0,  x2 + y2 – x + 6y + 5 = 0, x2 + y2 + 5x – 8y + 15 = 0 : Kaysons Education

# Find The Radical Centre Of The Circles, x2 + y2 + 3x + 2y + 1 = 0,  x2 + y2 – x + 6y + 5 = 0, x2 + y2 + 5x – 8y + 15 = 0

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## Question

### Solution

Correct option is

(3, 2)

Given circle are

x2 + y2 + 3x + 2y + 1 = 0                    …(1)

x2 + y2 – x + 6y + 5 = 0                      …(2)

xâ€‘2 + y2 + 5x – 8y + 15 = 0                 …(3)  Equation (1) – (2)

4x – 4y – 4 = 0                                   …(4)

Equation (2) – (3)

Equation (1) – (3)

Equation (4) + (6)

4y = 8

y = 2

From (4)

x – 2 = 1

x = 3

So the radical centre of the circle is (3, 2).

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