Tentukan pusat & jari jari lingkaran X²+y²-10x-6y-11=0

Diket :
A = -10
B = -6
C = -11

* Pusat lingkaran
= (1/2.A , 1/2.B)
= (1/2.(-10) , 1/2.(-6))
= (-5,-3)

*Jari jari lingkaran
r = √1/4A + 1/4B - C
= √1/4.(-10) + 1/4.(-6) + 11
= √-10/4 - 6/4 + 11
= √-16/4 + 11
= √-4 + 11
= √8
= 2√3