The Cones ClipArt gallery offers 62 examples of three-dimensional geometric solids that are made by taking all straight lines from the apex (top) at an angle to a plane in a 360 degree radius. A cone has a circular base, and looks like a triangle when viewing them from only the x and y axis.
Intersection of Two Cones
"The cone B would be developed by cutting a right section as S—S whose stretchout will be a circle…