# Thread: lateral edges of a pyramid

1. ## lateral edges of a pyramid

Hi,
I wonder if each lateral edge of a pyramid can be perpendicular to one of base's edge? The base is a tetragon. (If it is possible what a tetragon should it be and if it is not why)

This is my first post so I want you to be understanding

2. Originally Posted by Oloria
Hi,
I wonder if each lateral edge of a pyramid can be perpendicular to one of base's edge? The base is a tetragon. (If it is possible what a tetragon should it be and if it is not why)

This is my first post so I want you to be understanding
if each lateral face of a pyramid is a triangle, then how would it be possible for a lateral edge to be perpendicular to a base edge?

3. "each lateral edge of a pyramid can be perpendicular to one of base's edge"
The base is a four sided figure.

It doesn't mean that perpendicular straight lines has to cross themselves like it is required on a facet. Though, they should be perpendicular to one of base's edge. Each lateral edge should be perpendicular to one of base's edge. In space two lines can be perpendicular even if they aren't crossed in a drawing.

I think it is possible, but I was trying so many times with no result. Surely, it can't be a square. I was trying with a trapezoid, but as I wrote, I didn't find a correct one.

how would it be possible for a lateral edge to be perpendicular to a base edge?
You consider too obvious cases. Each lateral edge won't abut to a perpendicular (to it) base edge. But they will be perpendicular in space.