Curriculum placement
Algebra 2. This describes the skill, not a learner estimate.
Solving radical equations
Solve radical equations and reject extraneous candidates
Problem types
- Solve equations with cube roots
- Enter a radical-equation solution
- Check solutions after squaring
- Solve an equation with two square roots and reject the extraneous value
- Show the work: an equation with two square roots and an extraneous solution
Builds on
Leads to
- Solving a linear and a nonlinear equation together · See it applied
Solving a radical equation is finding the intersection of a root curve with another curve, and extraneous solutions are points that do not lie on both.
Related skills
- Approximating a solution from a graph · Related idea
Extraneous roots appear when squaring an equation, and a graph shows which solutions are real intersections.
- Finding an inverse function · Related idea
Squaring undoes a square root, which is why solving radical equations works and why extraneous solutions must be checked.
- Completing the square · Shared foundations
- Quadratic, rational, and exponential constraints · Shared foundations
- Graphs of quadratic functions · Shared foundations
Open the interactive map to explore lessons and skill connections.