Lesson 4: Factoring Trinomials of the Form ax^2 + bx + c

Math 10C Module 3 Lesson 4

Module 3: Polynomials

Launch

Are You Ready?

Complete these questions in your course folder (binder). If you are experiencing difficulty, you may want to use the information and the multimedia in the Refresher section to clarify concepts before completing these exercises.

1. Arrange the terms into two pairs so that each pair has the greatest possible common factor.
a. 2x³, 3x², 3, 2x
b. 21x³, 2y, 6x²y, 7x
c. 1, xy, x, y
d. 10ax, 4ay, 15x, 6y

2.   Find the products.
a.   2x(x + 1)
b.   (x + 3)(x - 2)
c.   3(x + 2)(2x - 5)

3. Find two numbers whose product and sum are indicated in the table. The first row has been done as an example.

	Product	Sum	Integers
Example	10	7	5 and 2
a.	20	-9
b.	-12	1
c.	-60	11

4.   Factor the following
a.   15x²y² + 25x³y²
b.   x² - 8x - 9
c.   2x² + 6x - 20

Once you have completed these exercises to the best of your ability, use the provided answer link to check your work.
Answers
If you feel comfortable with the concepts covered in the questions, move forward to Discover. If you experienced difficulties or want more practice, use the resources in Refresher to review these important concepts before continuing through the lesson or contact your teacher.

Refresher

The purpose of this section is to provide you with some resources to review in preparation for the lesson ahead. These resources may include videos, interactive applets, mini-lessons, and flash games to help you recall previously learned concepts. You can use these resources either before or after you try the Are You Ready? questions. Your teacher may also direct you to this section to review specific concepts.

Watch the “Mathcast 007 Greatest Common Factor” . You can move through the first examples until you find the ones that cover polynomial CF.

-------------------------------------------------------------------

Watch the “Mathcast 005 Using an Area Model to Illustrate the Multiplication of a Binomial and a Binomial” . Watch the video to see how you can use algebra tiles to model the multiplication of binomials.

-------------------------------------------------------------------

Watch this short video" Factoring Trinomials using the Product Sum method" that gives some help on how to be sure you have the entire set of factors when factoring a trinomial.

Materials

For this lesson, you may wish to use the set of algebra tiles that you borrowed from your teacher or that you created from the Algebra Tiles Template.

Alternatively, you could continue to use the “Arranging Algebra Tiles” applet.