Education Technology

The Box Method

Published on 08/11/2010

Activity Overview

Students discover how to factor a quadratic function using the Box Method.

Key Steps

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    The document begins with a quadratic expression with a = 12,

    b = –13, and c = –4. Each successive page will instruct students how to create a "box" with organized terms that will lead to the factors of the polynomial.

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    A spreadsheet helps the student to find a pair of factors that add to the linear term. Even negative and positive numbers may be tested to find the correct pair. In this case, 3 and –16 works, while no other pair has a sum of –13x.

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    The values are stored so that the next few steps can be completed by the student.

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    When the box is complete, the binomial pairs are found on the outside of the box, and should be checked by expanding.