What area remains when a square of side (x) is removed from a square of side (x+6)?
Answer and explanation
Correct answer: \(12x+36\)
The larger square has area \((x+6)^2\), and the smaller square has area \(x^2\). Thus, the remaining area is \((x+6)^2-x^2\). Expanding gives \(x^2+12x+36-x^2=12x+36\). In \(6x+36\), the middle term is incorrect because \(2\times x\times 6=12x\). Exam tip: you can also use \(a^2-b^2=(a-b)(a+b)\) for such questions.
Frequently asked questions
What is the correct answer to this question?
\(12x+36\)
Why is this the correct answer?
The larger square has area \((x+6)^2\), and the smaller square has area \(x^2\). Thus, the remaining area is \((x+6)^2-x^2\). Expanding gives \(x^2+12x+36-x^2=12x+36\). In \(6x+36\), the middle term is incorrect because \(2\times x\times 6=12x\). Exam tip: you can also use \(a^2-b^2=(a-b)(a+b)\) for such questions.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Exploring Algebraic Identities. Topic: Visual models of identities.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
