Hexagon
The hexagon has six corners and six sides.
Each diagonal runs from one corner of the shape to an opposite corner, so each diagonal requires 2 corners. So in a hundred cornered shape there will be half of a hundred diagonals, which is 50. Just divide the number of corners by 2. So for a hexagon, which has 6 sides and 6 corners, there are 3 diagonals.
Many 3d shapes have a corner.
A shape with one corner is a triangle. Yes, I know, technically it has three sides, but it only has one corner. So, there you have it, a triangle is the shape you're looking for.
Wich 3 D shape has a corner on it?
triangle
A teardrop shape?
A diagonal.
The corner on a shape where edges meet is called a vertex.
Any polyhedron.
Possibly a cone
rectangle. * * * * * Since a rectangle is NOT a 3-D shape, the answer is clearly wrong. Many 3-d shapes have a corner.