An icosahedron is a polyhedron has 20 faces, and is a 3D shape.
Probably a mis-spelling of icosahedron. That is a 3-dimensional figure bounded by 20 regular (equilateral) triangles.
a crescent has 19 sides
how many sides does an polygonshave
10 sides.
There is no formula for how many sides there are in a polygon; the name of the polygon shows how many sides it has.
How many sides does a Decahedron Have
3Three.
"no" sides.
Polygon means "many sides."
4 sides
How many parallel sides has a trapezium?