Question

A cone is sliced exactly in half from the vertex to a diameter of the base. What shape is formed?

Answer 1

1. If you're looking for a one-dimensional answer, then the answer would be a triangle (if you're looking at the surface of the cut). The three sides would be the diameter and the slant heights.

2. Again, if you're looking for a one-dimensional answer, the answer would be a rectangle. The four sides would be the diagonals and the heights.

Hope this helps and sorry I couldn't reply sooner!