Question

3. Find the equation of the circle whose centre is (1, 2) and which passes through the point
(4, 6).​

Answer 1

The answer is in attached photo.

Answer 2

Step-by-step explanation:

Here,

r^2 = (4-1)^2 + (6-2)^2

or, r^2 = 9+16

or, r^2 = 25

i.e. r= 5 units

We know,

Equation of circle is

(x-h) ^2 + (y-k)^2 = r^2

or, (x-1)^2 + (y-2)^2 = 5^2

or, x^2 - 2x +1 +y^2 - 4y +4 =25

or, x^2 +y^2 - 2x - 4y +5-25=0

i.e. x^2 +y^2 - 2x - 4y - 20=0 is req. equation of circle.