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Learning Math Home
Measurement Session 6: Area Introduction
Session 6 Part A Part B Part C Homework
measurement Site Map
Session 6 Materials:

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:


Rectangle: A = l • w


Right triangle: A =

Stop!  Do the above problem before you proceed.  Use the tip text to help you solve the problem if you get stuck.
Think about the rectangle method you used on the geoboard to find the area of a right triangle.   Close Tip

Next > Part B (Continued): The Triangle Formula

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