1. Finding Area and Perimeter
Pre-algebra
Grade 7

2. Tangrams Learning Objectives Calculate areas by counting squares
Calculate area using formulas
Use the correct language for shapes, attributes and formulas

3. The Tangram is made from cutting a square into 7 pieces1 3 4 2 5 7 6
Write down the mathematical name for each of the 7 pieces.
Can you place the pieces in order of size, with the largest first?

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

5. Calculate the area and perimeter of the tangram
Method 1: counting squares
Method 2: Formulas: Perimeter – the sum of the sides
Rectangle – A= bh

6. 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

7. Click on the rectangle to see a solution
Rearrange the 7 pieces of the tangram to make a rectangle
Click on the rectangle to see a solution
Write down the area and the perimeter of the rectangle.
Area - A = bh

8. Rearrange the 7 pieces of the tangram to make the following shapes
Trapezoid
Parallelogram
Right triangle

9. Write down the area and the perimeter of the parallelogram.
Back
Write down the area and the perimeter of the parallelogram.
Area - A = bh

10. Write down the area and the perimeter of the trapezoid.
Back
Write down the area and the perimeter of the trapezoid.
A= ½ h(b1 + b2)

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

12. Now that you have gathered your data, fill in the Area and Perimeter worksheet.
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.
Draw a diagram of the polygon and label it.
Indicate what lines you used to determine the area.
Area
Perimeter

13. Have extra time? Want to explore?
Try these!! Add them to your worksheet for extra credit
An animal from the story
Pentagon
Make a design of your own
Hexagon
Right Angled Triangle
Find the area and perimeter of each shape.

14. Back

15. Back

16. This Powerpoint adapted from Tangrams Area and Perimeter contributed to TES Connect by davecavill.
Retrieved from
© D Cavill
2005