Teaching Algebra with Manipulatives

Using Overhead Manipulatives
(Use with Algebra 1, Lesson 8-7)
Multiplying Polynomials
Objective Model products of binomials.
Materials
• product mat transparency*
• algebra tiles*
• transparency pen*
• blank transparency
* available in Overhead Manipulative Resources
Demonstration 1
Product of Two Binomials
x
1
1 1 1
• Tell students you want to find (x 1)(x 4).
• Display the product mat transparency. Use algebra
tiles to mark a width of x 1 and a length of x 4.
x
1
• Using the marks as a guide, draw a large rectangle
and cover it with tiles. Ask students what polynomial
is modeled. x 2 5x 4 Ask what the product of
x 1 and x 4 is. x 2 5x 4
x 1
x 4
x 2 x x x x
x
1 1 1 1
Teacher Demonstration 2
Product of Two Binomials
x x 1
1 1
• Tell students you want to find (x 2)(2x 3).
• On the product mat, use tiles to mark a width of
x 2 and a length of 2x 3.
x
1
1
(continued on the next page)
Algebra 1—Chapter 8
© Glencoe/McGraw-Hill 145 Teaching Algebra with Manipulatives