In the plane, we have everywhere. So in the equation of the sphere, we have
which is a circle centered at (2, -10, 0) of radius 4.
In the plane, we have , which gives
But any squared real quantity is positive, so there is no intersection between the sphere and this plane.
In the plane, , so
which is a circle centered at (0, -10, 3) of radius .
B is equivalent to t = 8 + 2h