Quadratic Formula and Discriminant

The discriminant is

• aX²  + bX  +  c
• b - 4ac
• b² - 4ac
• b² + 4ac

Tags

CCSS.HSA-REI.B.4B

Determine the value of the discriminant and describe the number and type roots for the following:

x² + 7x + 13

• 101, 2 real roots

• 3, 2 real roots

• -101, 2 imaginary roots

• -3, 2 imaginary roots

Use the quadratic formula to solve 2x² + 2x - 12?

• -2, 3
• 2, 3
• 2, -3
• -2, -3

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.

Tags

CCSS.HSA-REI.B.4B

• A
• B
• C
• D

Solve Using the Quadratic Formula
 x² + 4x - 40 = -8

• -10 & -4
• -4 & 10
• -8 & 4
• 8 & -4

Tags

CCSS.HSA-REI.B.4B

What does the discriminant tell us?

• The maximum or minimum

• The y-intercept

• The number and type of solutions

• The axis of symmetry

Tags

CCSS.HSA-REI.B.4B

What are the solutions to x² - 3x = 5?

• 
• 
• 
• 

Tags

CCSS.HSA-REI.B.4B

Use the quadratic formula to determine the solutions.

2x² - 9x - 35 = 0

• x = 7/2, x = -6

• x = -5/2, x =5

• x = -3/7, x =6

• x = -5/2, x = 7

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

• Get factored form
• Write down: a=1, b=6, c=-13
• Make it equal 0 by subtracting 3 on each side
• Type it all in a calculator.