top of page
Factoring Simple Trinomials: x2+bx+c

Many polynomials such as 5x2+2x+1 can be written as the product of two binomials of the form (x+r) and (x+s)

 

 

Keep in mind, when factoring a polynomial of the form ax2+bx+c(when a=1), we want to find the following..

 

1) Two numbers that ADD to give b                         *Also referred as product and sum*

2) Two numbers that MULTIPLY to give c

 

 

To help you understand this concept more clearly, use product and sum. 

 

For example: x2+5x(Sum)+6(Product)                          _3_ x _2_ = 6

                   =(x+3)(x+2)                                                    _3_ + _2_ = 5

 

*Note if the product and sum do not equal to each other, its known as 'not possible'

 

For example: x2+2x+7

-Therefore, not possible     

 

 

Now lets practice:

 

 

1) x2-29x+28                                             2) x2+6x+5                           

 

 

 

 

 3) x2-52x+100                                       4) x2-10x+8

 

               

 

Answers:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Factoring Complex Trinomials a≠1

Complex Trinomials have a coefficient besides than 1 in front of the x2 term

 

Before we can solve a Complex Trinomial, we have to learn the concept of the following;

1) Binomial common factoring

2) Factor by Grouping

 

Binomial common factoring:

 

Example 1: 3x(2x-3)-2(2x-3)

            = (2x-3)(3x-2) < Basically here we collected the like terms which were(2x-3)  and put brackets on the left over variables which were (3x-2)

 

Now lets practice:

 

 

1) 2x(z-1)+3x(z-1)                    2) 4x(3x+4)-2(3x+4)              

  

 

 

  3) 7x(2x-6)+5(2x-6)             4) 5x(5x-1)+5(5x-1)  

 

Answers: 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Factoring by grouping: 

 

Example 1: (ef+dg) (eg+df) [ There is no common factor amongest each brackets]

 

*However we can group the variables that have a common factor*

= (ef+df)(eg+dg) [Now we can common factor]

= f(e+d)+g(e+d)

[Now we use Binomial common factoring]

= (e+d)(f+g)

 

For solving a complex trinomial we can solve it with two methods:

1) Decomposition Method

2) Trial and Error 

 

Decomposition Method:                                                                       Trial and Error: 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Now lets practice ( Preferred Decomposition)

 

1) 5x2-14x+8                                                                         2) 10y2-9x+2        

 

 

 

 

 

3) 16x2+26x+12 [Always remember to common factor] 

 

 

 

 

 

                

 

                                

 

 

 

 

 

 

                       

 

 

 

 

 

 

 

               

 

© 2023 by Name of Site. Proudly created with Wix.com

  • Facebook App Icon
  • Twitter App Icon
  • Google+ App Icon
bottom of page