Factoring Trinomials

Factoring Trinomials

Multiple Choice

In order to factor the trinomial ,  $x^2+bx+c$  we need to find to integers that....?

• add to b

• add to c

• subtract to b

• subtract to c

Multiple Choice

 $x^2+bx+c$  

The integers then must also.....

• Multiply to b

• Multiply to c

• Divide to b

• Divide to c

As an example, if we have

 $x^2+7x+12$  

Integers that sum to 7 are:   $0+7,\ 1+6,\ 2+5,\ 3+4$  
Factors of 12 are:   $1\cdot12,\ 2\cdot6,\ 3\cdot4$  

The only pair that are in common are  3 and 4.  

This means we can factor it to:   $\left(x+3\right)\left(x+4\right)$  

Multiple Choice

Factor
a² - a - 12

• (a - 4)(a + 3)
• (a + 6)(a - 4)
• (a - 6)(a + 4)
• (a + 4)(a - 3)

Multiple Choice

Factor
x² + 9x - 36

• (x + 12)(x - 3)
• (x + 9)(x - 4)
• (x - 12)(x + 3)
• (x - 9)(x - 4)

Multiple Choice

Factor
n² + 5n - 6

• (n - 2)(n - 3)
• (n - 1)(n + 6)
• (n + 1)(n - 6)
• (n + 2)(n - 3)

Multiple Choice

Factor:
x² + 7x - 30

• (x + 10)(x - 7)
• (x - 10)(x + 3)
• (x + 10)(x + 3)
• (x + 10)(x - 3)

Multiple Choice

Factor completely.
3x² - 9x -120

• 3(x - 8)(x + 5)
• 3(x + 8)(x - 5)
• (3x + 8)(x - 5)
• (3x - 8)(x + 5)