6-5 The Quadratic Formula and the Discriminant B

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

Tags

CCSS.HSA.REI.B.4

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

• True

• False

Tags

CCSS.HSA-REI.B.4B

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.

Tags

CCSS.HSA-REI.B.4B

The discriminant is

• b² + 4ac

• b² - 4ac

• b - 4ac

• ax²  + bx  +  c

Tags

CCSS.HSA-REI.B.4B

Solve using the Quadratic Formula:

15x² + 22x = −8

Tags

CCSS.HSA-REI.B.4B

If the discriminant equals 0, then the quadratic has:

• 1 Real Solution

• 2 Real Solutions

• 2 Irrational Solutions

• 2 Complex Solutions

Tags

CCSS.HSA-REI.B.4B

If the discriminant is negative, then the quadratic has:

• 1 Real Solution

• 2 Real Solutions

• 2 Irrational Solutions

• 2 Complex Solutions

Tags

CCSS.HSA-REI.B.4B

A function has a discriminant of 25.

How many solutions does it have?

• 0

• 1

• 2

• 5

Tags

CCSS.HSA-REI.B.4B

A function has a discriminant of -3.

How many x-intercepts does it have?

• 0

• 1

• 2

• 3

Tags

CCSS.HSA-SSE.B.3B

CCSS.HSF-IF.C.8A

Suzanne solved the equation using this process.

Did she make a mistake?

If yes, at which line did she make her first mistake?

(There are 5 steps in her process)

• Suzanne made no errors.

• Step 2

• Step 3

• Step 4

• Step 5

Tags

CCSS.HSA-REI.B.4B