### Area and Perimeter of Regular Polygons

*Square*

**Content Objective:**

Students will rediscover the method of finding
the perimeter and area of squares.

**Materials:**

Rulers for pairs, square
perimeter worksheet, square area worksheet

**Procedure:**

### Perimeter

1. Collectively recall the definition of perimeter
given on review day. Have students get into pairs and distribute
perimeter worksheet. Once worksheet is complete and students have
compared their answers, ask the class as a whole the following
questions:

What do you notice about the side lengths
of our squares?

What happens to the perimeter when the side
lengths are changed?

Is there a way to find the perimeter of a
square without measuring all four sides? What if you were only
given the length of the diagonal, how would you find the side
lengths?

2. Demonstrate using Geometer's Sketchpad the
properties of the side lengths of squares. Click here
to use the GSP file.

### Area

1. Collectively recall the definition of area
given on review day. Now, have students get back into pairs and
distribute area worksheet. Once worksheet is complete and students
have compared their answers, ask the class as a whole the following
questions:

Again, what do you notice about the side lengths
of our squares?

What happens to the area when the side lengths
are changed?

How is the length of one side related to the
area of the square?

Is there a way to find the area of a square
with one side length? What about with only the length of the
diagonal?

2. Demonstrate using Geometer's Sketchpad the
properties of the base and altitude of regular triangles. Click
here to use the GSP file.

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