Units 7 & 8 Review

What is the first question you ask yourself when factoring a polynomial? 

• How many terms does it have? 

• Is there a GCF? 

• What strategy should I use? 

• Why do I have to learn this?!?!?!

Factor completely:

x² + 9x - 36

• (x + 12)(x - 3)

• (x + 9)(x - 4)

• (x - 12)(x + 3)

• (x - 9)(x - 4)

Factor completely:

81m² - 1 

• not factorable

• (m-9)(m+9)

• 9m(9m-1)

• (9m-1)(9m+1)

A rectangle has an area of 2x² – 19x +45 ft². What are the dimensions of the rectangle?  

• (2x - 9)(x - 5)
• (2x + 9)(x + 5)
• (2x - 5)(x - 9)
• (2x - 5)(x + 9)

What are the factors of
25x² - 81?

• (5x - 9)(5x + 9)
• (5x - 9)(5x - 9)
• (5x + 9)(5x + 9)
• Cannot be factored

Factor:
10x² + 9x - 7

• (5x + 10)(2x - 7)
• (10x + 2)(x - 3)
• (5x + 3)(2x + 1)
• (5x + 7)(2x - 1)

What is the first step in solving 
(x + 2)(x - 3) = 0      ?

• Plug in zero for x
• Solve for x
• FOIL
• Set each binomial factor equal to zero

Solve for the values of x:
(x + 2)(x - 3) = 0

• { 2, 3 }
• { -2, -3 }
• { 2, 3 }
• { -2, 3 }

Solve and find your zeros:
z(z - 15)=0

• z=0 and z=15
• z=0 and z=-15
• z=-15
• z=15