 Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum  MENU                    Exploring Communication  Introduction | Finding the Area of Different Figures | Try It Yourself: Finding the Area of Dot-Paper Shapes | Summary | Your Journal    To find the area of a figure, we need to determine the number of square units that make up that figure. For example: Area = 2 square units Finding the area is straightforward when the figure is a rectangle, such as the one above or the one below: Area = 15 square units

 How would you find the area of the following figure? Try not to use a formula; rather, think of how to rearrange the figure to form a shape whose area is easier to calculate (count). Show Answer
 Sample Answer: The area can be easily counted if we rearrange the parallelogram into a rectangle, as shown below. The area of the rectangle, and thus the parallelogram, is 6 square units. Think about what you just did with the parallelogram. Describe with pictures and words the answers to the following questions. Remember, the focus here is on communication, so your answers need to clearly communicate your thinking and the process you used to solve the problem.

1. What makes finding the area of a parallelogram more difficult than finding the area of a rectangle?

2. Explain how you found the area of the parallelogram. How did you deal with the parts of square units that were "hanging off the edge"?

3. What would be another way to count the total area? Explain your new method in words and with a drawing.  Try this as an Interactive activity       Teaching Math Home | Grades K-2 | Communication | Site Map | © |        © Annenberg Foundation 2017. All rights reserved. Legal Policy