Solid (3D) Figures

I can identify, classify, and compare three dimensional geometric figures using appropriate terminology and vocabulary.

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ESSENTIAL QUESTIONS

• What are 3 dimensional geometric figures? How are they classified?

• What are 3 dimensional geometric figures? How are they related to polygons?

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Let’s Review Polygons

• What makes geometric shapes (polygons) different from each other?

• We never looked at circles, ovals, or anything with curved sides. Do you know why these shapes weren’t included with polygons?

• Why is it important to know how many edges and vertices a polygon has?

Turn to your shoulder partner and tell them what you think about all these questions!

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What makes geometric shapes (polygons) different from each other? The number of sides, or edges, is what tells us what kind of polygon we have – triangle, quadrilateral, pentagon…

We never looked at circles, ovals, or anything with curved sides. Do you know why these shapes weren’t included with polygons?Polygons only include shapes with straight edges! But now we will be talking about these kinds of shapes.

Why is it important to know how many edges and vertices a polygon has?There is a direct relationship between how many edges and vertices a polygon has and what name it has – tri=3, quad=4, penta=5, hexa=6…

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Time to take notes

• We will be learning some basic terms today, take notes and draw & label pictures if you need to.

• We will cover:• Faces• Edges• Vertices• Prisms• Cubes• Pyramids• Curved Solids

Let’s go!

The sides of a solid figure are called faces.

face

Edges are formed when two faces meet.

edge

A vertex is formed where three or more edges meet.

vertex

Vertices is the plural form of vertex.

Polyhedron • A polyhedron is a solid with flat faces. figure

(from Greek poly- meaning "many" and -edron meaning "face").

• Each face is a polygon or 2-D figure. (a flat shape with straight sides).

• So, to be a polyhedron there should be no curved surfaces.

A prism is a polyhedron that has 2 congruent bases.

base - bottom face of a solid figure

Prisms are named according to their bases.

Base Name of Prism

triangle triangular prism

rectangle rectangular prism

hexagon hexagonal prism

This is a special prism called a cube. All of its faces are squares.It is a type of rectangular prism!

A pyramid is a polyhedron with only one base. All other faces are triangles that meet at the same vertex.

Pyramids are named according to their bases as well!

Base Name of Pyramid

triangle triangular pyramid

rectangle rectangular pyramid

pentagon pentagonal pyramid

Which is correctly labeled?

Circular Polyhedron

Square Prism

Rectangular prism

Let’s count the parts of a triangular prism.

Faces _______5

Edges ________9

Vertices _______6

Solids with curved surfaces are NOT polyhedrons.

Cylinder - a solid figure with two congruent circular faces

Cone - a solid figure with one circular base and one vertex

vertex

circular base

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A very special curved solid is called a Sphere – you just know it as a ball!

• A sphere has only one surface or face.

• It has no edges nor vertices.

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Closure• In your notebook, describe the attributes of

one three-dimensional geometric shape.

• Draw a picture of your shape after you write down its attributes.

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