The square root of 81 is:
A{'text': '7'}
B{'text': '9'}
C{'text': '8'}
D{'text': '10'}
Answer & Solution
Correct answer: B. {'text': '9'}
1. The square root of n is the number that, when multiplied by itself, gives n.
2. We test: 9 × 9 = 81.
3. So √81 = **9**.
4. Note 10 × 10 = 100, 8 × 8 = 64 — neither equals 81.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Square root definition_
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