Algebraic Expressions and Identities — Class 8 MCQs with Answers
Class 8 CBSE Mathematics · Chapter 108
Pre-2026 syllabusThis chapter is from the older NCERT book. See the 2026-27 Class 8 Mathematics chapters →
72 practice questions · 24 Easy · 24 Medium · 24 Hard · Updated
Practise the most important Class 8 CBSE Mathematics questions from Chapter 108, "Algebraic Expressions and Identities". You get 9 timed quizzes made from 72 NCERT-based MCQs, with answers and explanations. The questions are split into 24 Easy, 24 Medium and 24 Hard. Warm up on the basics, then move on to the exam-level questions that set top scorers in CBSE Board exams apart.
To score well in "Algebraic Expressions and Identities", focus on fast problem-solving, formula recall and step-by-step working. Each MCQ here is timed and uses exam-style marking (+4 correct, −1 wrong, 0 skipped). This trains you to stay accurate under time pressure, as real papers need. Every question has a short explanation, so a wrong answer becomes a quick lesson. It is the fastest way to fix gaps before a test.
Use this chapter for focused revision. Start with the Easy set to check your basics on Algebraic Expressions and Identities, then move to Medium and Hard to practise applying them. Your accuracy, streaks and XP save automatically. This chapter also adds to your overall Class 8 Mathematics mastery score. 14 sample questions are solved in full below, with the answer and a worked explanation. Sign in free to start practising.
Key concepts: Algebraic Expressions and Identities (Class 8 Mathematics)
This chapter covers algebraic terms and expressions, their addition, subtraction and multiplication, and the standard algebraic identities.
- Terms & expressions
- Monomials, binomials and trinomials are expressions with one, two and three terms; like terms have the same variables and powers.
- Operations
- Add/subtract by combining like terms; multiply using the distributive law term by term.
- Standard identities
- Special products that speed up expansion: (a+b)², (a−b)², (a+b)(a−b).
- Identity for (x+a)(x+b)
- (x+a)(x+b) = x² + (a+b)x + ab.
Algebraic Expressions and Identities — important questions & MCQs with answers (Class 8 Mathematics)
14 solved questions from this chapter's difficulty levels, each with its answer and explanation. The other 58 are timed and scored when you sign in.
- Q1Easy
In 3x²y, the coefficient is:
A.3✓ CorrectB.x²C.yD.x²yAnswer: A. 3
Explanation: Numerical part.
- Q2Easy
(a+b)² =
A.a² − b²B.a² − 2ab + b²C.a² + b²D.a² + 2ab + b²✓ CorrectAnswer: D. a² + 2ab + b²
Explanation: Standard identity.
- Q3Easy
What is the coefficient of x in the term −7xy²?
A.y²B.−7C.−7y²✓ CorrectD.7y²Answer: C. −7y²
Explanation: The coefficient of x is everything multiplying x, i.e. −7y².
- Q4Easy
(a−b)² =
A.a² − b²B.a² + 2ab + b²C.a² − 2ab + b²✓ CorrectD.a² + b²Answer: C. a² − 2ab + b²
Explanation: This is the standard square-of-a-difference identity.
- Q5Easy
Which pair below are like terms?
A.3xy and 3x²yB.5x²y and −2x²y✓ CorrectC.4ab and 4a²bD.2x and 2yAnswer: B. 5x²y and −2x²y
Explanation: Like terms have identical variables with identical powers; only 5x²y and −2x²y match.
- Q6Easy
Using an identity, (x+5)(x−5) =
A.x² + 25B.x² − 25✓ CorrectC.x² − 10x + 25D.x² − 5Answer: B. x² − 25
Explanation: By (a+b)(a−b) = a² − b², the product is x² − 25.
- Q7Medium
(2x)(3x) =
A.6x²✓ CorrectB.5x²C.6xD.6Answer: A. 6x²
Explanation: Multiply coefficients and add powers.
- Q8Medium
(a−b)(a+b) =
A.(a−b)²B.a² + b²C.a² − b²✓ CorrectD.(a+b)²Answer: C. a² − b²
Explanation: Difference of squares.
- Q9Medium
Multiply (x + 3)(x − 5).
A.x² − 2x − 15✓ CorrectB.x² + 2x − 15C.x² − 2x + 15D.x² − 8x − 15Answer: A. x² − 2x − 15
Explanation: x² + (3−5)x + (3)(−5) = x² − 2x − 15.
- Q10Medium
Expand (x + 3)².
A.x² + 6x + 6B.x² + 6x + 9✓ CorrectC.x² + 3x + 9D.x² + 9Answer: B. x² + 6x + 9
Explanation: (a+b)² = a² + 2ab + b² gives x² + 6x + 9.
- Q11Medium
Multiply: 2x(3x² − 4x + 1).
A.6x³ − 8x² + 1B.6x² − 8x + 2xC.6x³ − 8x² + 2x✓ CorrectD.5x³ − 8x² + 2xAnswer: C. 6x³ − 8x² + 2x
Explanation: Distribute 2x over each term: 6x³ − 8x² + 2x.
- Q12Hard
Simplify (x + 2)(x + 3) + (x − 1)(x − 4).
A.2x² + 10✓ CorrectB.2x² + 10x + 10C.2x² − 10D.2x² + 2x + 10Answer: A. 2x² + 10
Explanation: (x²+5x+6) + (x²−5x+4) = 2x² + 10.
- Q13Hard
Compute 102² using identity:
A.10404✓ CorrectB.10204C.10500D.10024Answer: A. 10404
Explanation: (100+2)² = 10000 + 400 + 4.
- Q14Hard
Expand and simplify (2x + 1)(x − 3) − (x + 2)(x − 1).
A.x² − 4x − 5B.x² − 6x + 1C.x² − 6x − 1✓ CorrectD.3x² − 6x − 1Answer: C. x² − 6x − 1
Explanation: (2x²−5x−3) − (x²+x−2) = x² − 6x − 1.
Start this chapter free
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This chapter has 72 questions (24 Easy · 24 Medium · 24 Hard), with timed scoring and instant feedback. The rest unlock with the ₹999/year plan.
Start this chapter free →Algebraic Expressions and Identities — FAQs
What are the key concepts in Class 8 Mathematics Algebraic Expressions and Identities?+
This chapter covers algebraic terms and expressions, their addition, subtraction and multiplication, and the standard algebraic identities. Key ideas include Terms & expressions, Operations, Standard identities, Identity for (x+a)(x+b).
What does Class 8 Mathematics Chapter 108 (Algebraic Expressions and Identities) cover on XamBaaz?+
It has 72 NCERT-based MCQs on "Algebraic Expressions and Identities": 24 Easy, 24 Medium and 24 Hard. Together they make 9 timed quizzes, and you never get the same set twice. Every question has an instant explanation. They help you prepare for CBSE Board exams.
Are these "Algebraic Expressions and Identities" questions free to practise?+
Yes. Sign in with Google to practise "Algebraic Expressions and Identities" free. Full unlimited access is ₹999/year on a launch offer until 1 December 2026. No chapter is charged separately.
How should I revise "Algebraic Expressions and Identities" for the exam?+
Start with the Easy quiz to check your basics, then try Medium and Hard to practise applying them. There are 9 timed quizzes on this chapter, so you can come back for a fresh set instead of one you have seen. Read each explanation, retry the questions you miss, and track your accuracy until it stays high.
Are these "Algebraic Expressions and Identities" MCQs available with answers?+
Yes. 14 sample questions are shown here in full, each with the correct option and a step-by-step "Why" explanation. Sign in free with Google to start practising, with instant scoring.
Is there negative marking in the "Algebraic Expressions and Identities" quizzes?+
Yes. The timed quizzes use exam-style marking: +4 for a right answer, −1 for a wrong one and 0 for a skip. MHT-CET and CBSE board papers have no negative marking. Our mocks for those are scored their way.
What are the important questions from Algebraic Expressions and Identities (Class 8 Mathematics)?+
The questions that matter most test Terms & expressions, Operations, Standard identities, Identity for (x+a)(x+b). This page shows 14 solved important MCQs with answers and explanations; all 72 questions on the chapter are available as timed quizzes once you sign in.
Is there an online quiz for Algebraic Expressions and Identities?+
Yes — Class 8 Mathematics Algebraic Expressions and Identities has timed online quizzes at Easy, Medium and Hard levels, with instant scoring and a worked explanation on every question. The first quiz on the chapter is free.