A piramid.
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Wrong! There cannot be such a polyhedron.
The Euler characteristic for polyhedra requires that F + V = E + 2 where F = faces, V = Vertices (or Corners) and E = Edges.
This requirement is not satisfied by the numbers given.
I AM A SPACE FIGURE WITH 5 FACES, 8 EDGES, AND 4 CORNERS. which SPACE FIGURE AM i?
pyramid
rectangular pyramid
4 corners 6 edges 4 faces
Faces = 4... Edges = 6... Corners... 4
It has 4 faces, 4 corners, and 4 edges, but two edges are different from each other. All the corners are right angles.
12 edges, 4 corners.
This is an impossible three-dimensional figure. A pyramid has 5 faces and 8 edges but has 5 corners, not 4. A 4-cornered three-dimensional figure has only one itteration: that of a 4 sided pyramid of 6 edges. Since your shape is 5 sided with 8 edges I would say you have got a number wrong there somewhere.
A tetrahedron, or triangle-based pyramid, has four corners, four faces and six edges.
A triangular-based pyramid has 4 corners, 4 faces and 6 edges.
5 faces 9 edges 6 corners
A triagular based pyramid has 4 corners, 6 edges and 4 faces