Quadratic Formula and Discriminant

Describe and correct the error a student made in solving an equation.

• The student used b instead of −b in the first term in the numerator when substituting values into the formula

• The student should have the equation as a(x−b)²+c=0 and then substituted those values into the Quadratic Formula.

• The student dropped the negative sign in simplifying the expression (−5)².

• The student used a instead of 2a in the denominator when substituting values into the formula.

Tags

CCSS.HSA-REI.B.4B

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

• -2, 3

• 2, 3

• 2, -3

• -2, -3

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

Tags

CCSS.HSA-REI.B.4B

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

• -10 & -4

• -4 & 10

• -8 & 4

• 8 & -4

Tags

CCSS.HSA-REI.B.4B

Solve using the quadratic formula...
9x² = 4 + 7x

• x = 2 and x = 3

• x = -1 and x = .25

• x = 1 and x = -.45

• x = 1.16, and x = -.38

Tags

CCSS.HSA-REI.B.4B

Use the quadratic formula to find the solutions for
y = -x² - 5x + 12

• -4.9 and -0.1

• -8.54 and 8.54

• -0.45 and 3.55

• -6.77 and 1.77

Tags

CCSS.HSA-REI.B.4B

If the discriminant is equal to 0, how many solutions are there?

• No solutions

• 1 Solution

• 2 Solutions

• Infinite solutions

Tags

CCSS.HSA-REI.B.4B

If the discriminant is equal to 4, how many solutions are there?

• No Solutions

• 1 Solution

• 2 Solutions

• Infinite Solutions

Tags

CCSS.HSA-REI.B.4B

If the discriminant is equal to -2, how many solutions are there?

• No Solutions

• 1 Solution

• 2 Solutions

• Infinite Solutions

Tags

CCSS.HSA-REI.B.4B

How many solutions does it have?

• 0

• 1

• 2

• Infinite

Tags

CCSS.8.EE.C.8B