Question 505281
equation of a circle:
(x - h)^2 + (y - k)^2 = r^2
.
For your problem:
x^2+y^2-12x+10y = -25
group x's and y's:
(x^2-12x)+(y^2+10y) = -25
complete the squares:
(x^2-12x+36)+(y^2+10y+25) = -25+36+25
(x-6)^2+(y+5)^2 = 36
(x-6)^2+(y+5)^2 = 6^2
.
Center: (6,5)
Radius: 6