Pre-Algebra Demystified

EXAMPLE

Multiply x(2xþ3y).

SOLUTION

xð2xþ3yÞ¼x2xþx3y

¼2x^2 þ3xy

EXAMPLE

Multiply 5x^2 y(3xþ2y
6)

SOLUTION

5x^2 yð3xþ2y
 6 Þ¼5x^2 y3xþ5x^2 y2y
5x^2 y 6

¼15x^3 yþ10x^2 y^2 
30x^2 y

PRACTICE

Multiply:

1. 8(2xþ2y
   6)


2. 4x(5x^2
   6xþ12)


3. 
   3xy^2 (2xyþ6x^2
   10)


4. 
   c^2 d^3 (3c^2 þ4cd
   5d^2 )


5. 6ab(3a
   2bþ4c^2 )

ANSWERS

1. 16xþ16y
   48


2. 20x^3
   24x^2 þ48x


3. 
   6x^2 y^3
   18x^3 y^2 þ30xy^2


4. 
   3c^4 d^3
   4c^3 d^4 þ5c^2 d^5


5. 18a^2 b
   12ab^2 þ24abc^2

Multiplication of Two Binomials

In algebra, there are some special products that you will need to know. The

first one is to be able to find the product of two binomials. In order to do this,

you can use the distributive law twice.

EXAMPLE

Multiply (xþ4) (xþ2).

240 CHAPTER 12 Monomials and Polynomials