JENECONKMaths Universe

Square Roots

Ages 9–13

Difficulty adapts to you

Square Roots

The symbol √ gives the principal, or non-negative, square root. It is the non-negative number that squares to make the given value.

Your goals

  • ✓You can find the square root of a number.
  • ✓You can use principal square root, radical sign correctly.
  • ✓You can square your answer to recover the starting number.

Words to know

principal square root:
The non-negative number whose square equals the given number.
radical sign:
The symbol √ used for a principal square root.

Examples

  • 1√9 = 3 because 3 × 3 = 9.
  • 2√25 = 5 and √144 = 12.

Check these

  • • Do not halve a number when you need its square root.
  • • Keep every number, symbol, label, and unit in its correct place.
  • • Show enough working to check how you reached your answer.

Helpful habits

  • • Read the whole question before choosing what to do.
  • • Show one clear step at a time and check each step.
  • • If you are stuck, draw a model, try smaller numbers, or revisit the example.

Now try your own

Create your own square roots example, solve it, and explain how you checked it.

Professor Wise Owl

Professor Wise Owl

Wisdom & Understanding

“Take your time — wisdom comes from understanding, not rushing!”