Answer to Question #97946 in Geometry for Rachel

Question

Give two definitions for both the plane and the sphere.

Answer 1

A plane is a surface that completely contains each line connecting its arbitrary points;

A plane is a set of points equidistant from two given points.

Sphere, a closed surface, all points of which are equally distant from one point (the center of the sphere).

A sphere, in geometry, is a three-dimensional analogue of a circle, a geometric solid generated by the rotation of a circle around its diameter.