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Grade 9 · Math · Algebra 1

9th grade Add, subtract and multiply square roots and cube roots worksheet

6 printable versionsBuilding Confidence10 questions · answer keyFree · no account

Level: Building Confidence · On Level · Challenge Me

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Add, subtract and multiply square roots and cube roots

Grade 9 Math Worksheet - Building Confidence

NameDate

Circle the best answer, or write your answer on the line.

  1. Kira's worksheet shows 3√5 + 4√5. The strip shows the copies of √5. What is the sum? Write it like 2√11.

  2. Luz's robot adds 2√7 + 6√7 (and beeps twice to show it is thinking). The strip shows the copies of √7. What is the sum? Write it like 2√11.

  3. Noah's padlock tag shows 4√2 + 5√2. The strip shows the copies of √2. What is the sum? Write it like 2√11.

  4. Pia's rug is √3 m wide and √27 m long, so its area is √3 × √27 square meters. It equals √(3 × 27). What whole number is √3 × √27?

  5. Ren's worksheet shows √5 × √20 (the answer is a whole number, the sheet promises). It equals √(5 × 20). What whole number is √5 × √20?

  6. Tala's robot multiplies √6 × √24 under one root. It equals √(6 × 24). What whole number is √6 × √24?

  7. In math club, Zee multiplies √7 × √28. It equals √(7 × 28). What whole number is √7 × √28?

  8. Bo's robot can only join like pieces. Which one can be written as a single root term?

    • 7√2 − 3√2
    • 7√2 − 3
    • 7√2 − 3√7
    • 7 − 3√2
  9. In math club, Esme looks at four expressions. Which one can be written as a single root term?

    • 5√6 + √5
    • 5√6 + √6
    • 5√6 + 6
    • 5 + √6
  10. Jun's padlock opens for the one that joins (the others just jiggle). Which one can be written as a single root term?

    • 9√5 − 2
    • 9 − 2√5
    • 9√5 − 2√5
    • 9√5 − 2√3
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9th grade Add, subtract and multiply square roots and cube roots worksheet – printable
Print: 123456

About this worksheet

Add, subtract and multiply square roots and cube roots. Every version has 10 questions, and the answer key prints on the second page.

What your child will learn

  • I can add 3√5 + 4√5 = 7√5 by counting copies of √5.
  • I can simplify √12 + √27 to 2√3 + 3√3 = 5√3.
  • I can multiply 2√3 × 5√6 = 10√18 = 30√2.

Standard: N-RN.A.2

Words to know

like roots: Roots with the same number underneath, like 3√5 and 4√5.

front number: The number in front of the root, the 3 in 3√5.

copies: 3√5 is three copies of √5 added together.

fully simplified: No pair (or triple) of equal factors is left under the root.

distribute: Multiply the number outside the brackets by every term inside.

Common mistakes

Your child added or subtracted the numbers under the roots, for example writing √10 for √2 + √8.

Your child multiplied the front numbers when adding like roots.

Your child multiplied the numbers under the roots and then forgot to take the square root.

What to say

Ask: is √9 + √16 the same as √25?

Ask: what are 3 apples plus 4 apples? Then 3√5 + 4√5?

Ask: what is √100?

Questions parents ask

What is the most common mistake with add, subtract and multiply square roots and cube roots?

Your child added or subtracted the numbers under the roots, for example writing √10 for √2 + √8.

How can I help my child with add, subtract and multiply square roots and cube roots?

Ask: is √9 + √16 the same as √25?

Are these 9th grade math worksheets free to print?

Yes. All 6 printable versions at each level are free to print, with the answer key, and no account is needed.

More algebra 1

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