Find the center and the radius of the circle x2 y2 6x2y90Sol

Find the center and the radius of the circle x^2 +y^2 -6x+2y+9=0

x^2 + y^2 -6x + 2y + 9 = 0

standard equation of circle is

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

where h , k is the centre of the circle

writing the equation in standard form

x^2 + y^2 -6x + 2y + 9 = 0

( x - 3)^2 - 9 + ( y +1)^2 - 1 + 9 = 0

(x-3)^2 + ( y+1)^2 = 1

therefore ,

centre = ( 3 , -1)

radius = 1