Which is the equation for a sphere with the center (2,-9,-1) and radius sqrt r? a.
(x + 2)^2 + (y - 9)^2 + ( z - 1)^2 = r
c.
(x - 2)^2 + (y + 9)^2 + ( z + 1)^2 = sqrt r
b.
(x - 2)^2 + (y + 9)^2 + ( z + 1)^2 = r
d.
(x + 2)^2 + (y - 9)^2 + ( z - 1)^2 = r^2

94

step-by-step explanation:

average the numbers and use a variable to figure out the minimum to get a 90.

(79+94+91+92+x)/5=90

x = 94

other answer is correct. i had used the radius of the radius somehow. a website:

answer: both chords and diameters have two endpoints on a circle. diameters must intersect the center of a circle.