Unit 6, Lesson 14

The Quadratic Formula and Complex Solutions

$Course Icon$

Integrated Math 2

14.1

Warm-up

Mentally decide whether the solutions to each equation are real numbers or not.

14.2

Activity

Kiran was using the quadratic formula to solve the equation . He wrote this:

Then he noticed that the number inside the square root is negative and said, “This equation doesn’t have any solutions.”

Do you agree with Kiran? Explain your reasoning.
Write as an imaginary number.
Solve the equation and plot the solutions in the complex plane.

<p>Complex plane. Horizontal axis, scale -4 to 4, by 2’s. Vertical axis, scale -4i to 4i, by 2i’s. </p>

14.3

Activity

For each row, you and your partner will each solve a quadratic equation. You should each get the same answer. If you disagree, work to reach an agreement.

partner A	partner B

Student Lesson Summary

Sometimes when we use the quadratic formula to solve a quadratic equation, we get a negative number inside the square root symbol. This means that the solutions to the equation must involve imaginary numbers. For example, consider the following equation:

Using the quadratic formula, we know that:

or

This means that the two solutions are:

and

None

Navigation

Gradeband

Course

Unit

Lesson

Settings

Audience

Assessment Access

Lesson | Loading...

Settings

Audience

Assessment Access

The Quadratic Formula and Complex Solutions

Warm-up

Activity

Activity

Student Lesson Summary