S and S′ are two intersecting spheres. The line BXB′ is parallel to the line of centers, where B is a point on S,B′ is a point on S′ and X lies on both spheres. A is another point on S, and A′ is another point on S' such that the line AA′ has a point on both spheres. Show that the segments AB and A′B′ have equal projections on the line AA′.
geometry3D geometrysphereprojection