Lesson 4

Lesson 4: Solving Radical Equations

 

Focus

 

Crash investigators can use the length of skid marks to determine the speed of a vehicle when the vehicle first applied its brakes. Investigators use radical equations, such as and , where s is speed, d is skid distance, f is drag factor, and v is velocity (or speed). This is just one of the many practical applications of radical equations.

 

In this lesson you will learn to solve equations containing radicals. The first three lessons in this module have prepared you to master this essential mathematical skill.

 

Outcomes

 

At the end of this lesson you will be able to

• determine any restrictions on values for the variable in a radical equation

• determine the roots of a radical equation algebraically, and explain the process used to solve the equation

• verify by substitution that the values determined in solving a radical equation algebraically are roots of the equation

• explain why some roots determined in solving a radical equation algebraically are extraneous

Lesson Questions

 

You will investigate the following questions:

• How do you determine the roots of a radical equation algebraically?
  
  
• How do you verify that the values determined in solving a radical equation are viable roots of the equation?

Assessment

Your assessment may be based on a combination of the following tasks:

• completion of the Lesson 4 Assignment (Download the Lesson 4 Assignment and save it in your course folder now.)
  
  
• course folder submissions from Try This and Share activities
  
  
• additions to Module 5 Glossary Terms and Formula Sheet
  
  
• work under Project Connection