## 3D Objects (Prisms, Cylinders, Cones, Spheres)

**Three‐dimensional objects **are the **solid shapes **you see every day, like boxes, balls, coffee cups, and cans.

Here are some helpful vocabulary terms for solids:

**Face**: a flat side of a 3‐dimensional object.**Base**: one of two parallel, congruent sides of an object.**Edge**: the intersection of two faces on a solid object. This is a line.**Prism**: a solid object with two congruent and parallel faces.**Pyramid**: a solid object with a polygon for a base and triangles for sides.

### Say Hello to the 3-D Shapes

**Name** | **Properties** | **Picture** |

**Rectangular Prism** | - A prism with rectangular bases.
- There are six faces.
- All faces meet at 90 degrees.
- Opposite faces are parallel.
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**Cube** | - A prism with six congruent faces.
- All faces meet at 90-degree angles.
- Opposite faces are parallel.
- It is a form of rectangular prism.
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**Triangular Prism** | - A prism with triangular bases.
- Only the bases are parallel.
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**Octagonal Prism** | - A prism with octagons for bases.
- Opposite faces are parallel.
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**Triangular Pyramid, aka Tetrahedron** | - A pyramid with a triangular base.
- A tetrahedron made up of four equilateral triangles is called a regular tetrahedron.
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**Square Pyramid** | - A pyramid with a square base.
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**Cylinder** | - A solid with two parallel circular bases.
- If you "unwrap" the middle section and lay it flat, it is a rectangle.
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**Cone** | - A solid with a circular base and a curved side that ends in one point
- It has one vertex.
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**Sphere** | - A solid figure where all points are an equal distance from the center point.
- It's a ball.
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