Bellwork

1 / 24

# Bellwork - PowerPoint PPT Presentation

Bellwork. Pannini’s Pizza Parlor advertises that you could get a one-topping pizza from them once a week for over two years and never have exactly the same pizza twice! Are they correct? Here is their menu

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about 'Bellwork' - miriam

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### Bellwork

Pannini’s Pizza Parlor advertises that you could get a one-topping pizza from them once a week for over two years and never have exactly the same pizza twice! Are they correct? Here is their menu

How many triangles are there in the 4, 5 and 6th triangles if there are 1 in the first, 3 in the second and 6 in the third?

1

2

3

4

### Bellwork Solution

Pannini’s Pizza Parlor advertises that you could get a one-topping pizza from them once a week for over two years and never have exactly the same pizza twice! Are they correct? Here is their menu

### Bellwork Solution

1

2

3

4

How many triangles are there in the 4, 5 and 6th triangles if there are 1 in the first, 3 in the second and 6 in the third?

### Lines of Symmetry

Section 5.α

The Concept
• Today we’re going to be talking about a relatively basic topic, but one that is very important to our discussion of geometry, specifically in regards to areas and three dimensional solids

Line of Symmetry

-Imaginary line drawn that creates a reproduced piece of an object

### Symmetry

There are primarily two kinds of lines of symmetry

• Bilateral
• Splits the object exactly in half
• Reproduces a piece of the object as it rotates about a center

### Symmetry

Let’s take a closer look at rotational symmetry

Instead of splitting an object up we look to cut it into pieces from a “center of symmetry”

This is done in such a way that each piece replicates itself as it’s rotated around

### Symmetry

Typically there is at most two ways to divide an object radially, although there are many ways to do it bilaterally

### Examples

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

What are lines of symmetry for this object

### Example

This looks a lot like a reflection…

One of the ways that lines of symmetry are used is in the process of drawing objects

For instance

### Drawing

A helpful Theorem for us to remember governs symmetry in regular polygons

Theorem 5.20: Lines of symmetry in regular polygons

The number of lines of symmetry in a regular n-gon is equal to the number of sides

### Homework

9.6

1-20, 27-30 (don’t figure angles)

Bilateral Symmetry