10/4 Quadratics, Factoring, Key Features

Find the zeros: x² = 7x + 18

• -7 and -18

• 9 and 2

• 9 and -2

• 2 and 7

Find the zeros:  2x²+ 7x + 6 = 0

• x= 3/2 and x = 2
• x = -3/2 and x = -2
• x = 6 and x = 7
• x = -6 and x = -7

Solve for x:

(x-5)(x+6)=0

• {5,5 }

• { -5,-5 }

• { -5,-6 }

• {5,-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 factors AND solutions of x² + 2x – 3 = 0

• (x - 2)(x + 1); x=2, x=-1
• (x + 1)(x - 3); x=-1, x=3
• (x + 2)(x - 1); x=-2, x=1
• (x - 1)(x + 3); x=1, x=-3

Find the roots.
x² - 9x = 0

• 9
• 0, 9
• -9, 0
• -9

What should you do first in solving this equation?
x² + 6x - 13 = 3

• Get factored form
• Find two numbers which add to make 6 and multiply to make -13
• Make it equal 0 by subtracting 3 on each side
• Type it all in a calculator.

Find the zeros.

n² - 2n = 0

• n = 2 and 0

• n = -2 and 0

• n = 2

• n = 0