Eleventh graders work with radical functions and equations — solving by isolating and squaring, watching for extraneous solutions that squaring can introduce, and finding the domain of a square-root function.
Students will be able to…
To solve √x = 5, you square both sides. But squaring can create fake answers! How do you solve radical equations safely — and why must you always check?
Project each item and have students solve or analyze the radical equation. The tool explains squaring, extraneous solutions, and domain.
Tap any phase to open the teacher moves and student actions.
To solve √x = 5, we square both sides — but is that always safe?
Teacher models.
Class uses Solve the Radical.
Students solve.
One equation.
Aligned to the Common Core State Standards for Mathematics (High School Algebra II).
Solve simple radical equations and give examples of extraneous solutions.
Graph square-root and other radical functions.
Create equations to solve problems.
Relate the domain of a function to its graph.
Preview the three formative checks. Tap “Sample answer” to see what mastery looks like — hide them before you print for students.
Have students solve equations with a radical on each side, isolating and squaring carefully, then checking. A printable radical-equations sheet is in the Math library.
Tap a card to flip it, then rate whether you knew it. Built from this lesson’s vocabulary.
A quick self-check with instant feedback, drawn from this lesson’s key terms.
A print-and-go review sheet with a built-in answer key. Tap “Show answer key” to reveal answers, or print the clean version for students.