use the distance formula for a) and b)find the distance between (3,7,-5) and (3,7,0)

we eliminated the z-component for the quickest way to the xy-plane

find the distance between (3,7,-5) and (3,0,-5)b)xz-plane

we eliminated the y-component for the quickest way to the xz-plane

use the midpoint formula for the two points. this will give you the center of the sphere. use the distance formula for the distance between the two points. half this distance is the radius2) Find an equation of a sphere if one of its diameters has endpoints (2,1,4) and (4,3,10).

then you know the equation of a sphere:

where is the center and is the radius