Question 184987
The locus of points (x, y, z) that are 2 units from a given point (4, -1, 1) describe a sphere whose center is at (4, -1, 1) and whose radius is 2 units.
The general form for a sphere with center at (h, k, l) and radius (r) is given by:
{{{(x-h)^2+(y-k)^2+(z-l)^2 = r^2}}} so for this problem, you have the equation:
{{{highlight((x-4)^2+(y+1)^2+(z-1)^2 = 4)}}}