Framing The Session Students will draw and find the area of two rectangles by counting squares within the figure. Students should record the length and width of each rectangle. From this chart of values, they should derive the formula for perimeter and area of the rectangles.
Teaching Demonstrate for participants how to use GSP to create rectangles and determine their areas: Step 1 – First, open Geometers Sketchpad. Step 2 – From the tool bar, select Graph. Step 3 – Select Define Coordinate System. Step 4 – Drag the graph so that only Quadrant I is visible. Step 5 – Select Snap Points from Graph menu. Step 6 – Select the line segment tool and use it on the grid to create two rectangles with perimeters of 12 inches but of different areas (problem 1). Step 7 – Count the squares to determine the perimeter and area. Label the rectangles.
Guided Practice Use Geometers Sketchpad to discuss problem 1 in IMPACT Math Course 1 page 495_2 nd ed.,2004 Problem Set A.
Getting Started Complete problems 2-4 in IMPACT Math Course 1 page 495_2 nd ed.,2004 Problem Set A using Geometers Sketchpad. Then go to C1 page 499_2 nd ed.,2004 Problem Set D. Use Geometers Sketchpad and open Squares and Square Roots. Use these to demonstrate the relationship between the sides of the square and the square root.Squares and Square Roots We will come back together and share.
Work Time Create a chart and record answers xx2x2 525 9 27 44 59 67 83
Work Time What formula would you use to find the area of a rectangle? What formula would you use to find the perimeter of a rectangle? Does your rule for rectangles hold true for squares? Why or why not?
Work Time Create different rectangles and squares on a grid in GSP. Record results in the table. Do your formulas work? LengthWidthPerimeterArea
Go to the IMPACT Self-Check Quiz website. Complete the quizzes for Course 1_2 nd ed.,2004 Chapter 8, sections 2 and 3. How would you use website in your classrooms?IMPACT Self-Check Quiz What are the advantages and drawbacks to using Geometers Sketchpad? Share
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