Question

Find the center and radius of x2 + y2 + 2x - 10y + 10 = 0

Answer 1

factorise it to get
(x+1)^2 + (y-5)^2 = 16 = 4^2

hence centre is (-1,5) and radius is 4

Answer 2

centre(-1,5) radius=4 using d general eqn of a circle=x^2+y^2-2ax-2bx+c=0 wen d centre is(a,b) radius=sqrt a^2+b^2-c

Answer 3

x^2+y^2+2x-10y+10=0
==>(x+1)^2+(y-5)^2+10-1-25=0
==>(x+1)^2+(y-5)^2=4^2
==>center is (-1,5), and rad=4