Finding Area and PerimeterPre-algebraGrade 7

Tangrams

Learning Objectives

Calculate areas by counting squares

Calculate area using formulas

Use the correct language for shapes, attributes and formulas

The Tangram is made from cutting a square into 7 pieces

13

4 2

5

67

Write down the mathematical name for each of the 7 pieces.

Can you place the pieces in order of size, with the largest first?

Draw a tangram on square cm paper starting with a 16 by 16 square

Calculate the area and perimeter of the tangram

Method 1: counting squares

Method 2: Formulas: Perimeter – the sum of the sides

Rectangle – A= bh

Calculate the area and perimeter of each of the 7 pieces of the tangram

Method 1: counting squares

Method 2: Formulas: Perimeter and area

Calculate the area and perimeter of each of the 7 pieces

Rearrange the 7 pieces of the tangram to make a rectangle

Write down the area and the perimeter of the rectangle.

Area - A = bh

Click on the rectangle to see a

solution

Rearrange the 7 pieces of the tangram to make the following shapes

Parallelogram

Trapezoid

Right triangle

Back

Write down the area and the perimeter of the parallelogram.

Area - A = bh

Back

Write down the area and the perimeter of the trapezoid.

A= ½ h(b1 + b2)

Back

Write down the area and perimeter of the triangle A= ½ h(b1 + b2),

Now that you have gathered your data, fill in the Area and Perimeter worksheet. Draw a diagram of the polygon and

label it. Indicate what lines you used to determine the area.

Area 

Perimeter

  

   

  

   

  

   

  

   

    

Directions: Use the data you have recorded in your journal to fill in the chart and answer the questions below.List the following polygons from greatest to least by area, square, rectangle, parallelogram, trapezoid, triangle.

Hexagon

Have extra time? Want to explore?

Try these!! Add them to your worksheet for extra credit

Make a design of your own

An animal from the story

Right Angled Triangle

Pentagon

Find the area and perimeter of each shape.

Back

Back

© D Cavill

2005

This Powerpoint adapted from Tangrams Area and Perimeter contributed to TES Connect by davecavill.Retrieved from http://www.sharemylesson.com/teaching-resource/Tangrams-Area-and-Perimeter-3012408/