Solving a Quadratic by the Quadratic Formula

Tags

CCSS.HSA-REI.B.4B

If b²-4ac is positive, the quadratic equation has:

• Two real solutions that are different

• Two imaginary solutions that are different

• One real solution

• One imaginary solution

Tags

CCSS.HSA-REI.B.4B

If b²-4ac is negative, the quadratic equation has:

• Two real solutions that are different

• Two imaginary solutions that are different

• One real solution

• One imaginary solution

Tags

CCSS.HSA-REI.B.4B

If b²-4ac is 0, the quadratic equation has:

• Two real solutions that are different

• Two imaginary solutions that are different

• One real solution

• One imaginary solution

Tags

CCSS.HSA-REI.B.4B

What are the zeros of the function f(x) = x² + 64?

• -8 and 8

• -8i and 8i

• (-√8) i and (√8) i

• -√8  and √8

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

Solve using the quadratic formula.

2x² - 9x - 35 = 0

• x = 7/2 and x = -6

• x = -5/2 and x =5

• x = -3/7 and x =6

• x = -5/2 and x = 7

Tags

CCSS.HSA-REI.B.4B

Use the quadratic formula to solve: n² = 9n - 20

• n = 4 and n = -5

• n = -4 and n = 5

• n = -4 and n = -5

• n = 4 and n = 5

Tags

CCSS.HSA-REI.B.4B

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

Solve by using the quadratic formula.

7x² - 26x - 8 = 0

• x = -1 and x = -7/8

• x = 4 and x = -2/7

• x = -4 and x = 2/7

• x = 4 and x = -7/2

Tags

CCSS.HSA-REI.B.4B