Question

The equation of the circle is (x+8)^2+(y+9)^2=169. Which of the following are the center and the radius of the circle

Answer 1

The equation for a circle is (x - h)^2 + (y - k)^2 = r^2
where (h, k) is the center and r is the radius
(x + 8)^2 + (y + 9)^2 = 169
Since the equation is -h and -k, I will rewrite in terms of -h and -k.
(x - -8)^2 + (y - -9)^2 = 13^2
The center is (-8, -9) and the radius = 13
Let me know if you need me to explain further.