Solving Quadratic Equations by Factoring EOC Review

Factor x²-16

• (x+4)²

• (x-4)²

• (x-16)(x+16)

• (x-4)(x+4)

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

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

Factor
3a² + 4a + 1

• (7a-10)(a-8)
• Not factorable
• (3a+1)(a+1)
• (3a-1)(a-1)

Factor
k² - 2k - 24

• (k+4)(k-6)
• (k+4)(k+6)
• (k+6)(k-1)
• (k-4)(k+6)

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

What are the values of x when y = 0?

• { -3, 1 }
• { -2 }
• { -3, -1 }
• { 1, 3 }

What are the x- intercepts?

• x= 0 and x= -4
• x= 0 and x= 4
• y= 0
• x= 2

Solve:
x² - 49 = 0

• x = -7, x = 7
• x = -7
• x = 7
• x = -7, x = 1

Convert x² - 9x + 20 to factored form and solve.

• (x-10)(x+2); x = -2, 10
• (x+4)(x+5); x = -5, -4
• (x-4)(x-5); x = 4, 5
• Not factorable