Which conclusion is correct if \(\sqrt{k}=12\)?
Answer and explanation
Correct answer: \((k=144)\) and \(k\) is a perfect square
From \(\sqrt{k}=12\), square both sides to get \(k=12^2=144\). Hence \(k\) is a perfect square (and an integer). Why other options are wrong: B and C give values (24 or 6) that do not satisfy the equation; D incorrectly states \(k=12\) and calls it irrational. Exam tip: when given \(\sqrt{\,\cdot\,}\), square both sides to remove the root—remember the principal square root is nonnegative.
Frequently asked questions
What is the correct answer to this question?
\((k=144)\) and \(k\) is a perfect square
Why is this the correct answer?
From \(\sqrt{k}=12\), square both sides to get \(k=12^2=144\). Hence \(k\) is a perfect square (and an integer). Why other options are wrong: B and C give values (24 or 6) that do not satisfy the equation; D incorrectly states \(k=12\) and calls it irrational. Exam tip: when given \(\sqrt{\,\cdot\,}\), square both sides to remove the root—remember the principal square root is nonnegative.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Polynomials. Topic: Irrational numbers and real numbers.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
