# Math Help - equation of a spere in R^3

1. ## equation of a spere in R^3

One diameter of a sphere has endpoints (-5,6,-2) and (9,-4,0) Find the equation of this sphere.

Am I correct?

(X-h)² + (y-k)² + (z-L)² = r²
r = sqrt(300)
center = (2,1,-1)

thus,

(X-2)² + (y-1)² + (z+1)² = 75

is the 75 correct??

thank you

2. Originally Posted by VkL
One diameter of a sphere has endpoints (-5,6,-2) and (9,-4,0) Find the equation of this sphere.
center = (2,1,-1)
thus, (X-2)² + (y-1)² + (z+1)² = 75
is the 75 correct??
Yes that is correct. Because the radius is $\sqrt{75}$ not $\sqrt{300}$.