1. Openera-d) True or false. If false, explain with a statement or sketch.

a) A polygon with ten sides is a decagon.

b) If the sum of two angles is 180°, then they are complementary.

c) A pentagon has five sides and six diagonals.

d) The largest chord of a circle is also the circle’s diameter.

e) What are the next two elements of this sequence?

f) What is the 400th element of this sequence?

1.8 SPACE GEOMETRY

AB

CD

EA

2. Notes - 3D Drawings

Prisms Pyramids

Two congruent, parallel bases.

One base and one vertex.

2. Notes - 3D Drawings

Cylinder Cone

Two congruent, parallel circular bases.

2. Notes - 3D Drawings

Cylinder Cone

One base and one vertex.Two congruent, parallel circular bases.

2. Notes - 3D Drawings

Sphere Hemisphere

3. Classwork – sketch:

8.1 Sketch Me Now!

4. Notes: Nets

A net is a two-dimensional pattern that you can cut and fold to form a three-dimensional figure

4. Notes - 3D Drawings

4. Notes - 3D Drawings

5. Classwork

5. Classwork

5. Classworkpg. 83 // #1 - 7, 13 – 21

5. Classwork

6. A cross section is the intersection of a solid and a plane. You can think of a cross section as a very thin slice of the solid.

Describe this cross section.

The plane is parallel to the triangular base of the figure, so the cross section is also a triangle.

10-2

Draw and describe a cross section formed by a vertical plane intersecting the top and bottom faces of a cube.

If the vertical plane is parallel to opposite faces, the cross

section is a square.

Sample: If the vertical plane is not parallel to opposite faces,

the cross section is a rectangle.

Describing a Cross Section

What is the cross section formed by the plane and the solid below?

How can you see the cross section?

Mentally rotate the solid so that the plane is parallel to

your face.

Think-Pair-Share

Draw a cross section formed by a vertical plane intersecting the front and right faces of the cube. What shape is the cross section?

6.8.3 Cross Sections