Solving Quadratic Equations

Solve by factoring and zero product property:

x² - 9x + 20 = 0

• x = -4 and x = -5

• x = 20 and x = -9

• x = 4 and x = 5

• x = -4 and x = 5

Solve for x by factoring and

zero product property.

x² + 6x + 8 = 0

• x = -2, -4

• x = 2, 4

• x = 8, 1

• x = -8, -1

Solve for x:

(Hint: Take square root of both sides)

(x + 6)² = 49

• x=7,12

• x=±7

• x=1,-13

• x=43,-55

What is the first step to solving THIS equation by completing the square?
a² + 10a + 21 = 0

• Set the equation equal to zero
• Divide 10 by 2 and add the result to both sides
• Add a² and 10a together
• Subtract the 21

Tags

CCSS.HSA.REI.A.1

CCSS.HSA.REI.B.4

Solve by completing the square.
x² + 4x= 12

• x = 2 and -2
• x = -6 and 2
• x = 6 and -2
• x = 1 and -1

Tags

CCSS.HSA.REI.A.1

CCSS.HSA.REI.B.4

CCSS.HSA.SSE.A.2

Solve by completing the square. 
 x² − 10x - 11= 0

• x = −1 and 11
• x = 1 and −11
• x = −10 and 11
• x = −5 and 25

Tags

CCSS.HSA.REI.B.4

What is this formula?

• This is the speed of light formula.
• This is the quadratic formula.
• This is the zero product property.
• This is scary.

The quadratic equation can be used to solve quadratic equations that cannot be factored.

• True
• False

ax²+bx+c=0  is the standard form of a quadratic equation.

• True
• False

Tags

CCSS.HSA.CED.A.1

CCSS.HSA.REI.B.4

Determine the values of
a, b, and c for
the quadratic equation: 
4x² – 8x = 3

• a = 4, b = -8, c = 3
• a = 4, b =-8, c =-3
• a = 4, b = 8, c = 3
• a = 4, b = 8, c = -3