1.

2.

Quick Start Expectations

Come in and sit quietly.

Fill in planner and HWRS: 3.

p. 54&57; #12-13, 20

Read today’s target question:

Which regular polygons can be used to tile a surface without overlaps or gaps? How do you know your answer is correct?

3.

Work on

Warm-up

Warm-up Answers

S =

Angle Sum

S = 180 (n - 2) or S = 180n - 360 3 4 5

Measure of EACH Angle Angle Sum ÷ Number of Sides A = 180 (n – 2)

n or

A = 180n – 360

n or

A = 180 - 360

n

3 4 5

o Online Tessellation Activity In your notes, list the polygons that work and don’t work.

What is the measure of each angle in a regular polygon of n sides?

A = 180 (n – 2)

n

What is the sum of the measures of the angles around each vertex point in a tiling?

360º How do the answers to the first two questions explain the different results when tiling is attempted with different polygons?

The angles that meet in a tiling are equal and must be factors of 360º

The measure of all the angles coming together equals 360 degrees .

Pentagons, heptagons, octagons The measure of the interior angles increase .

No, because the angles coming together will be too large. They won’t combine to be 360 degrees.

The measure of all the angles coming together equals 360 degrees.

Homework

Textbook:

CMP3 Grade 7

Unit:

Shapes and Designs p. 54&57; #12-13, 20