4. Polyhedra A polyhedron is a solid made of flat surfaces. Each surface is a polygon. Examples: Platonic solids - tetrahedron Cube (hexahedron) octahedron dodecahedron icosahedron
5. polyhedra 2. Prisms - A prism has the same cross section all along its length ! Square prism Triangular prism Pentagonal prism
6. Pyramids Pyramids - a solid shape or structure that has triangular sides that slope to meet in a point and a base that is often, but not necessarily, a square
7. Parts of pyramid A pyramid is made by connecting a base to an apex
9. Non Polyhedra Non polyhedra- Some solids have curved surfaces, or a mix of curved and flat surfaces (so they aren't polyhedra). Examples: Sphere Cylinder Torus Cone
10. sphere Sphere -a three-dimensional closed surface consisting of all points that are a given distance from a center Properties: It is perfectly symmetrical It has no edges or vertices All points on the surface are the same distance from the center
11. cylinder Cylinder – an object or shape with straight sides and circular ends with equal size It has a flat base and a flat top The base is the same as the top, and also in-between It has one curved side Because it has a curved surface it is not a polyhedron.
12. Torus Torus- a ring shaped surface It can be made by revolving a small circle along a line made by another circle. It has no edges or vertices It is not a polyhedron
13. Cone Cone- has a circular based and tapers to a point at the top or has a circular top and tapers to a point at the bottom. It has a flat base It has one curved side Because it has a curved surface it is not a polyhedron.
14. Prepared by: NEIL B. MEMITA Teacher III San Isidro High School Lupao, Nueva Ecija Philippines
