U8A Solving Equations by Factoring

Which of the following mean the same thing as "roots?"

• x-intercepts

• zeros

• y-intercepts

• solutions

Factor:

x² + 11x + 24

• (x + 6)(x + 4)

• (x + 12)(x + 2)

• (x - 8)(x - 3)

• (x + 8)(x + 3)

What are the factors of 3x²-17x+10

• (x-5)(3x-2)
• (x+5)(3x+2)
• (3x-5)(x-2)
• (x+5)(3x-2)

Find the factors of 5x²+20x+20

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

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 - 3)(x + 6) = 0

• { -3, -6 }
• { 3, -6 }
• { -3, -6 }
• { 3, 6 }

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

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

Solve:

3x² + 18x +15 = 0

Hint: Factor GCF first.

• x = 3, 2

• x = 5, 1

• x = -5, -1

• x = -3, -2

Solve:

x² +0x - 49 = 0

• x = -7, x = 7

• x = -7

• x = 7

• x = -7, x = 1