Education Technology

Solving Equations with Two Radicals

Published on 10/20/2009

Activity Overview

Students will follow a model of how to solve by isolating first one radical, then the other, and squaring both sides. The CAS eliminates the common mistakes students encounter when squaring binomials that include radicals.

Before the Activity

How many solutions might the student expect, given an equation with an unpredictable or unknown graph?
How does squaring a binomial with one radical help the equation to be solved? Why must the isolating process occur twice in this strategy?
Students must have solved radical equations with a radical on just one side first. The students must be able to verify solutions, and perhaps compare the graph with the correct number of solutions.

After the Activity

Assessment and Evaluation:

  • The student document can be collected through the Connect to Class software and used as Formative assessment.
  • Further summative assessment can include equations with radicals on just one side or both sides.
  • Be sure that students are checking their answers to eliminate extraneous solutions.

  • Activity Extensions:
  • Have a student "teach" the concept to another student who was absent
  • Have students write their own equations and solve them