Factoring Trinomials

​Factoring Trinomials

By Susan Price

Bell Ringer discussion

1. Define the term sum.

2. What are factors of a number?

3. Determine if the answer to the equation would be negative or positive?​

   1. negative + negative=

   2. negative ​+ positive=

   3. negative * negative=

   4. negative * positive=​

5 minutes

What are the factors of the following numbers?

10 15 20 24 36

​

​Which factor pair of 10 have a sum of 7?

Which factor pair of 15 have a sum of 8?

W​hich factor pair of 20 have a sum of 21?

Which factor pair of 36 have a sum of 12?​

Trinomials

• Have 3 distinct terms

• Can also be called polynomials

• For factoring it helps if they are written in decending exponential order with a positive lead coefficient

Lead Coefficents and A/C method

Lead coefficients are the coeffient (or numerical factor) of the term with the highest exponent. For A/C method it is important that you identify your lead coefficient becuase that is also your A value. The C vlaue is the constant term at the end of your trinomial. This is another reason why it is important that you write you trinomial in descending exponential order.

Multiple Choice

What formula do we use to identify the "a", "b", and "c" when factoring?

• ax² +bx + c

• ax² +cx + b

• bx² +ax + c

• cx² +bx + a

Factoring Trinomials with No Common Factor when a>1

Multiple Choice

To factor the trinomial 6x² + 11x +3, start by multiplying "a" times "c" and identifying "b".

• true

• false

Math Response

Factor: $$3x^2-13x+4$$

Type answer here

Correct Answer: \left(x-4\right)\left(3x-1\right)

Deg^°

Rad

Multiple Choice

Factor Completely:  6x² + 5x - 6

• 6(x + 1)(x - 6)

• (6x + 6)(x - 1)

• (2x - 3)(3x + 2)

• (3x - 2)(2x + 3)

Multiple Choice

Factor completely: 
3x² + 18x +15
Hint: Factor GCF first.

• 3(x² + 6x + 5)
• (x + 5)(x + 1)
• 3(x + 5)(x + 1)
• Prime

Multiple Choice

Factor
x² +17x - 60

• (x - 20)(x + 3)
• (x + 12)(x - 5)
• (x - 12)(x + 5)
• (x + 20)(x - 3)

Multiple Choice

Factor:
x² + 4xy + 4y²

• (x + y)(4x + 4y)
• (x + 2y)(x + 2y)
• (2x + y)(2x + y)
• (x + 2)(x + 2)

Open Ended

Which step is the hardest for you?