 Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum            Session 6, Part B:
Exploring Area With a Geoboard

In This Part: Subdividing Area | The Rectangle Method | Formulas | The Triangle Formula

 Most of us use formulas to determine the area of common polygons, such as triangles and rectangles. The formula for the area of a rectangle is A = l • w, where l represents the length of the rectangle and w represents the width. The formula, for the area of a triangle is where b represents the length of the base of the triangle and h represents the height of the triangle. (Height is the length of the segment from a vertex perpendicular to the opposite side.) Problem B6 Explain how the formulas below relate to using the geoboard to find an area:

a.

Rectangle: A = l • w

b.

 Right triangle: A =   Think about the rectangle method you used on the geoboard to find the area of a right triangle.   Close Tip Think about the rectangle method you used on the geoboard to find the area of a right triangle.   Session 6: Index | Notes | Solutions | Video