XamBaaz
Try for Free
🧮

Class 9 Mathematics — Chapter 11: Lines and Angles

90 practice questions · 30 Easy · 30 Medium · 30 Hard

Practise Class 9 Mathematics Chapter 11, "Lines and Angles", with 90 NCERT-aligned multiple-choice questions. The set is split into 30 Easy, 30 Medium and 30 Hard questions, so you can warm up on the fundamentals and then push into the exam-level problems that separate top scorers in CBSE Board exams and the JEE & NEET foundation years.

"Lines and Angles" is one of the chapters where problem-solving speed, formula recall and step-by-step reasoning really pays off. Each MCQ on this chapter is timed and uses exam-grade marking (+2 correct, −1 wrong, 0 skipped), training the same accuracy-under-pressure that real papers demand. Every question carries a short explanation, so a wrong answer becomes a quick lesson rather than a dead end — the fastest way to close gaps before a test.

Use this chapter as targeted revision: attempt the Easy set first to confirm your basics on Lines and Angles, then move to Medium and Hard to test application and problem-solving. Your accuracy, streaks and XP save automatically, and the chapter feeds into your overall Class 9 Mathematics mastery score. A few sample questions are shown below; sign in free to practise all 90.

Key concepts: Lines and Angles (Class 9 Mathematics)

This chapter derives surface areas and volumes of solids — cuboid, cube, cylinder, cone, sphere and hemisphere — and applies them to real objects.

Surface area types
Curved (lateral) surface area excludes the flat ends; total surface area includes them.
Right circular cone
Slant height l relates to radius and height by l² = r² + h²; needed before finding the cone's surface area.
Sphere and hemisphere
A sphere is fully curved; a hemisphere adds a flat circular face, so its total surface area includes that circle.
Volume
The space a solid occupies, measured in cubic units; used in capacity and material problems.

Key formulas — Lines and Angles

Cuboid
TSA = 2(lb + bh + hl), V = l·b·h
Cube
TSA = 6a², V = a³
Cylinder
CSA = 2πrh, TSA = 2πr(r + h), V = πr²h
Cone
CSA = πrl, TSA = πr(l + r), V = ⅓πr²h
Sphere / Hemisphere
Sphere: SA = 4πr², V = 4⁄3 πr³; Hemisphere: TSA = 3πr², V = 2⁄3 πr³

💡 Exam tips for Lines and Angles

  • For a cone, find slant height l = √(r² + h²) before using the surface-area formula.
  • Watch the difference between curved and total surface area — the question usually specifies which.

Sample questions

Q1Easy

When a transversal cuts two parallel lines, corresponding angles are:

A.Supplementary
B.Complementary
C.Equal✓ correct
D.Right angles
Why

Corresponding angles are equal when a transversal crosses parallel lines.

Q2Medium

If l ∥ m and a transversal makes an angle of 55° with l, find the alternate interior angle with m.

A.55°✓ correct
B.125°
C.35°
D.90°
Why

Alternate interior angles are equal when lines are parallel. So the angle is also 55°.

Q3Hard

AB ∥ CD. A transversal cuts them. If one alternate interior angle is (3x−10)° and the other is (2x+15)°, find x.

A.25✓ correct
B.30
C.20
D.35
Why

Alternate interior angles are equal: 3x−10=2x+15→x=25.

Lines and Angles — FAQs

What are the key concepts in Class 9 Mathematics Lines and Angles?+

This chapter derives surface areas and volumes of solids — cuboid, cube, cylinder, cone, sphere and hemisphere — and applies them to real objects. Key ideas include Surface area types, Right circular cone, Sphere and hemisphere, Volume.

What does Class 9 Mathematics Chapter 11 (Lines and Angles) cover on XamBaaz?+

It covers 90 NCERT-aligned MCQs on "Lines and Angles" — 30 Easy, 30 Medium and 30 Hard — each with a timed quiz and an instant explanation, suitable for CBSE Board exams and the JEE & NEET foundation years.

Are these "Lines and Angles" questions free to practise?+

Yes — sign in with Google to practise "Lines and Angles" free. Full unlimited access is ₹999/year (limited-time launch price), with no per-chapter charges.

How should I revise "Lines and Angles" for the exam?+

Start with the Easy quiz to confirm your fundamentals, then attempt Medium and Hard for application-level practice. Review each explanation, retry the questions you miss, and track your accuracy on this chapter until it is consistently high.

Practise all 90 questions free

Timed quizzes, instant scoring, streaks and XP. Sign in with Google — no card needed.

Start this chapter free →

More Class 9 Mathematics chapters

← All Class 9 Mathematics chapters