Question

Tabitha defines a sphere as the set of all points equidistant from a single point. Is Tabitha's definition valid?

answer; it is valid because all spheres fit this definition, and figures that are not spheres do not fit this definition.

Answer 1

definition is valid since center is exactly 1radius away from any point on the outersurface.

other figures do not fit this defn

Answer 2

Tabitha's defintion is valid.

Explanation:

Her definition is valid because the sphere is basically defined by its radius, which is the equidistant points towards a center. If points are not equidistant, then that's not a sphere.

Also, Tabitha is considering "a set of points" referring to infinite points on the surface of the sphere. The single point she mentioned is the center.

Therefore, Tabitha's definition is valid because she's considering all elements that define a sphere.