Find the center and radius of the sphere.
-$$x ^ { 2 } + y ^ { 2 } + z ^ { 2 } - 8 x - 2 y + 8 z = 3$$
A) C(4, 1, 4), a = 6
B) C(4, 1, -4), a = 6
C) C(4, 1, -4), a = 36
D) C(-4, -1, 4), a = 6

Question

Quizplus · Accepted Answer

The equation of a sphere is $(x-h)^2 + (y-k)^2 + (z-l)^2 = r^2$. Completing the square for each variable, we find the center $C(4, 1, -4)$ and radius $a = 6$.

Find the Center and Radius of the Sphere x2+y2+z2−8x−2y+8z=3x ^ { 2 } + y ^ { 2 } + z ^ { 2 } - 8 x - 2 y + 8 z = 3x2+y2+z2−8x−2y+8z=3

Find the Center and Radius of the Sphere $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } - 8 x - 2 y + 8 z = 3$