2.09 The Quadratic Formula

2.09 The Quadratic Formula

Day 1

Lesson Agenda

• Do Now - slide 2 (3 min)

• Edgenuity Warm-Up (8 min)

• Lesson Objectives - slide 5 (2 min)

• Edgenuity Instruction (30 min)

• Exit Ticket (2 min)

Multiple Choice

Simplify

 $x\ =\ \frac{5+\sqrt{-49}}{6}$  

•  $-\frac{1}{3}i$  

•  $2i$  

•  $\frac{5}{6}+\frac{7}{6}i$  

•  $\frac{5}{6}-\frac{7}{6}i$  

Solutions and Intercepts

The parabola has ___ x-intercepts, representing the times when the ball’s height above the ground is ___ feet.

There are _____ solutions to this equation, representing the number of seconds elapsed between the ball leaving the group and hitting the ground again.

Fill in the Blanks

The parabola has

x-intercepts.

Fill in the Blanks

The x-intercepts represent the times when the ball’s height above the ground is

feet.

Fill in the Blanks

There are

solutions to this equation, representing the number of seconds elapsed between the ball leaving the group and hitting the ground again.

Edgenuity Video

Slide 2

Notes

Using the Quadratic Formula

Open Ended

Given

 $y=\left(2x+3\right)^2$ , identify the standard form of the quadratic equation.

Open Ended

Given  $0=4x^2+12x+9$ , what are a, b, and c?

Open Ended

Given $a=4,\ b=12,\ c=9$ .

Substitute into the quadratic formula.

  $x=\frac{-b+-\sqrt{b^2-4ac}}{2a}$   

Fill in the Blanks

The solution to  $0=4x^2+12x+9$ is

. 

Edgenuity Video

Slide 6

Multiple Choice

There are two real solutions if the radicand is ___.

• Less than zero

• Zero

• Greater than zero

Multiple Choice

There is one real solution if the radicand is ___.

• Less than zero

• Zero

• Greater than zero

Multiple Choice

There are zero real solutions (two complex solutions) if the radicand is ___.

• Less than zero

• Zero

• Greater than zero